Vulnerability-Lookup

BDU:2026-07293 (CVE-2026-20171)

Vulnerability from fstec – Published: 2026-05-26 – Updated: 2026-05-26 – View on bdu.fstec.ru Fixed

Title

Уязвимость протокола Border Gateway Protocol (BGP) операционной системы Cisco NX-OS маршрутизаторов Cisco Nexus 3000 Series Switches и Cisco Nexus 9000 Series Switches, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость протокола Border Gateway Protocol (BGP) операционной системы Cisco NX-OS маршрутизаторов Cisco Nexus 3000 Series Switches и Cisco Nexus 9000 Series Switches связана с ошибками обработки разрешений. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, вызвать отказ в обслуживании

Severity

5.4 (Medium) CVSS 2.0


                      
                        AV:N/AC:H/Au:N/C:N/I:N/A:C

6.8 (Medium) CVSS 3.1


                      
                        CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Resource manipulation

Consequences

Denial of service

Incidents

Being clarified

Remediation

Software update

CWE

CWE-670 - Реализация некорректного потока управления

Aliases

CVE-2026-20171

References

1 reference

URL
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/c…

Impacted products

1 product from 2 vendors

Vendors

Cisco Systems, Inc.

Products

NX-OS

Versions

10.2(1) (NX-OS), 10.2(1q) (NX-OS), 10.2(2) (NX-OS), 10.2(3) (NX-OS), 10.2(2a) (NX-OS), 10.2(3t) (NX-OS), 10.2(4) (NX-OS), 10.2(5) (NX-OS), 10.2(3v) (NX-OS), 10.2(6) (NX-OS), 10.2(7) (NX-OS), 10.2(8) (NX-OS), 10.2(9) (NX-OS), 10.3(1) (NX-OS), 10.3(2) (NX-OS), 10.3(3) (NX-OS), 10.3(99w) (NX-OS), 10.3(3w) (NX-OS), 10.3(99x) (NX-OS), 10.3(3o) (NX-OS), 10.3(4a) (NX-OS), 10.3(3p) (NX-OS), 10.3(4) (NX-OS), 10.3(3q) (NX-OS), 10.3(3x) (NX-OS), 10.3(5) (NX-OS), 10.3(4g) (NX-OS), 10.3(3r) (NX-OS), 10.3(6) (NX-OS), 10.3(4h) (NX-OS), 10.3(7) (NX-OS), 10.3(8) (NX-OS), 10.4(1) (NX-OS), 10.4(2) (NX-OS), 10.4(3) (NX-OS), 10.4(4) (NX-OS), 10.4(5) (NX-OS), 10.4(4g) (NX-OS), 10.4(6) (NX-OS), 10.5(1) (NX-OS), 10.5(2) (NX-OS), 10.5(3) (NX-OS), 10.5(3t) (NX-OS), 10.5(3e) (NX-OS), 10.5(3o) (NX-OS), 10.5(3s) (NX-OS), 10.5(3p) (NX-OS), 10.6(1) (NX-OS), 10.6(1s) (NX-OS)

Product types

Operating system

Platforms

Cisco Systems, Inc. NX-OS 10.2(1) Nexus 3000 Series, Inc. NX-OS 10.2(1q) Nexus 3000 Series, Inc. NX-OS 10.2(1) Nexus 9000 Series, Inc. NX-OS 10.2(1q) Nexus 9000 Series, Inc. NX-OS 10.2(2) Nexus 3000 Series, Inc. NX-OS 10.2(3) Nexus 3000 Series, Inc. NX-OS 10.2(2a) Nexus 3000 Series, Inc. NX-OS 10.2(3t) Nexus 3000 Series, Inc. NX-OS 10.2(4) Nexus 3000 Series, Inc. NX-OS 10.2(5) Nexus 3000 Series, Inc. NX-OS 10.2(3v) Nexus 3000 Series, Inc. NX-OS 10.2(6) Nexus 3000 Series, Inc. NX-OS 10.2(7) Nexus 3000 Series, Inc. NX-OS 10.2(8) Nexus 3000 Series, Inc. NX-OS 10.2(9) Nexus 3000 Series, Inc. NX-OS 10.3(1) Nexus 3000 Series, Inc. NX-OS 10.3(2) Nexus 3000 Series, Inc. NX-OS 10.3(3) Nexus 3000 Series, Inc. NX-OS 10.3(99w) Nexus 3000 Series, Inc. NX-OS 10.3(3w) Nexus 3000 Series, Inc. NX-OS 10.3(99x) Nexus 3000 Series, Inc. NX-OS 10.3(3o) Nexus 3000 Series, Inc. NX-OS 10.3(4a) Nexus 3000 Series, Inc. NX-OS 10.3(3p) Nexus 3000 Series, Inc. NX-OS 10.3(4) Nexus 3000 Series, Inc. NX-OS 10.3(3q) Nexus 3000 Series, Inc. NX-OS 10.3(3x) Nexus 3000 Series, Inc. NX-OS 10.3(5) Nexus 3000 Series, Inc. NX-OS 10.3(4g) Nexus 3000 Series, Inc. NX-OS 10.3(3r) Nexus 3000 Series, Inc. NX-OS 10.3(6) Nexus 3000 Series, Inc. NX-OS 10.3(4h) Nexus 3000 Series, Inc. NX-OS 10.3(7) Nexus 3000 Series, Inc. NX-OS 10.3(8) Nexus 3000 Series, Inc. NX-OS 10.4(1) Nexus 3000 Series, Inc. NX-OS 10.4(2) Nexus 3000 Series, Inc. NX-OS 10.4(3) Nexus 3000 Series, Inc. NX-OS 10.4(4) Nexus 3000 Series, Inc. NX-OS 10.4(5) Nexus 3000 Series, Inc. NX-OS 10.4(4g) Nexus 3000 Series, Inc. NX-OS 10.4(6) Nexus 3000 Series, Inc. NX-OS 10.5(1) Nexus 3000 Series, Inc. NX-OS 10.5(2) Nexus 3000 Series, Inc. NX-OS 10.5(3) Nexus 3000 Series, Inc. NX-OS 10.5(3t) Nexus 3000 Series, Inc. NX-OS 10.5(3e) Nexus 3000 Series, Inc. NX-OS 10.5(3o) Nexus 3000 Series, Inc. NX-OS 10.5(3s) Nexus 3000 Series, Inc. NX-OS 10.5(3p) Nexus 3000 Series, Inc. NX-OS 10.6(1) Nexus 3000 Series, Inc. NX-OS 10.6(1s) Nexus 3000 Series, Inc. NX-OS 10.2(2) Nexus 9000 Series, Inc. NX-OS 10.2(3) Nexus 9000 Series, Inc. NX-OS 10.2(2a) Nexus 9000 Series, Inc. NX-OS 10.2(3t) Nexus 9000 Series, Inc. NX-OS 10.2(4) Nexus 9000 Series, Inc. NX-OS 10.2(5) Nexus 9000 Series, Inc. NX-OS 10.2(3v) Nexus 9000 Series, Inc. NX-OS 10.2(6) Nexus 9000 Series, Inc. NX-OS 10.2(7) Nexus 9000 Series, Inc. NX-OS 10.2(8) Nexus 9000 Series, Inc. NX-OS 10.2(9) Nexus 9000 Series, Inc. NX-OS 10.3(1) Nexus 9000 Series, Inc. NX-OS 10.3(2) Nexus 9000 Series, Inc. NX-OS 10.3(3) Nexus 9000 Series, Inc. NX-OS 10.3(99w) Nexus 9000 Series, Inc. NX-OS 10.3(3w) Nexus 9000 Series, Inc. NX-OS 10.3(99x) Nexus 9000 Series, Inc. NX-OS 10.3(3o) Nexus 9000 Series, Inc. NX-OS 10.3(4a) Nexus 9000 Series, Inc. NX-OS 10.3(3p) Nexus 9000 Series, Inc. NX-OS 10.3(4) Nexus 9000 Series, Inc. NX-OS 10.3(3q) Nexus 9000 Series, Inc. NX-OS 10.3(3x) Nexus 9000 Series, Inc. NX-OS 10.3(5) Nexus 9000 Series, Inc. NX-OS 10.3(4g) Nexus 9000 Series, Inc. NX-OS 10.3(3r) Nexus 9000 Series, Inc. NX-OS 10.3(6) Nexus 9000 Series, Inc. NX-OS 10.3(4h) Nexus 9000 Series, Inc. NX-OS 10.3(7) Nexus 9000 Series, Inc. NX-OS 10.3(8) Nexus 9000 Series, Inc. NX-OS 10.4(1) Nexus 9000 Series, Inc. NX-OS 10.4(2) Nexus 9000 Series, Inc. NX-OS 10.4(3) Nexus 9000 Series, Inc. NX-OS 10.4(4) Nexus 9000 Series, Inc. NX-OS 10.4(5) Nexus 9000 Series, Inc. NX-OS 10.4(4g) Nexus 9000 Series, Inc. NX-OS 10.4(6) Nexus 9000 Series, Inc. NX-OS 10.5(1) Nexus 9000 Series, Inc. NX-OS 10.5(2) Nexus 9000 Series, Inc. NX-OS 10.5(3) Nexus 9000 Series, Inc. NX-OS 10.5(3t) Nexus 9000 Series, Inc. NX-OS 10.5(3e) Nexus 9000 Series, Inc. NX-OS 10.5(3o) Nexus 9000 Series, Inc. NX-OS 10.5(3s) Nexus 9000 Series, Inc. NX-OS 10.5(3p) Nexus 9000 Series, Inc. NX-OS 10.6(1) Nexus 9000 Series, Inc. NX-OS 10.6(1s) Nexus 9000 Series

Mitigations

Использование рекомендаций производителя: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bgp-iefab-3hb2pwtx

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:H/Au:N/C:N/I:N/A:C",
  "CVSS 3.0": "AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Cisco Systems, Inc.",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "10.2(1) (NX-OS), 10.2(1q) (NX-OS), 10.2(2) (NX-OS), 10.2(3) (NX-OS), 10.2(2a) (NX-OS), 10.2(3t) (NX-OS), 10.2(4) (NX-OS), 10.2(5) (NX-OS), 10.2(3v) (NX-OS), 10.2(6) (NX-OS), 10.2(7) (NX-OS), 10.2(8) (NX-OS), 10.2(9) (NX-OS), 10.3(1) (NX-OS), 10.3(2) (NX-OS), 10.3(3) (NX-OS), 10.3(99w) (NX-OS), 10.3(3w) (NX-OS), 10.3(99x) (NX-OS), 10.3(3o) (NX-OS), 10.3(4a) (NX-OS), 10.3(3p) (NX-OS), 10.3(4) (NX-OS), 10.3(3q) (NX-OS), 10.3(3x) (NX-OS), 10.3(5) (NX-OS), 10.3(4g) (NX-OS), 10.3(3r) (NX-OS), 10.3(6) (NX-OS), 10.3(4h) (NX-OS), 10.3(7) (NX-OS), 10.3(8) (NX-OS), 10.4(1) (NX-OS), 10.4(2) (NX-OS), 10.4(3) (NX-OS), 10.4(4) (NX-OS), 10.4(5) (NX-OS), 10.4(4g) (NX-OS), 10.4(6) (NX-OS), 10.5(1) (NX-OS), 10.5(2) (NX-OS), 10.5(3) (NX-OS), 10.5(3t) (NX-OS), 10.5(3e) (NX-OS), 10.5(3o) (NX-OS), 10.5(3s) (NX-OS), 10.5(3p) (NX-OS), 10.6(1) (NX-OS), 10.6(1s) (NX-OS)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f:\nhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bgp-iefab-3hb2pwtx",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "20.05.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "26.05.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "26.05.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-07293",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2026-20171",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "NX-OS",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Cisco Systems, Inc. NX-OS 10.2(1) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(1q) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(1) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(1q) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(2) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(3) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(2a) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(3t) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(4) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(5) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(3v) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(6) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(7) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(8) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(9) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(1) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(2) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(99w) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3w) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(99x) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3o) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(4a) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3p) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(4) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3q) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3x) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(5) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(4g) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(3r) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(6) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(4h) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(7) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.3(8) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(1) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(2) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(3) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(4) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(5) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(4g) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.4(6) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(1) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(2) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3t) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3e) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3o) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3s) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.5(3p) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.6(1) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.6(1s) Nexus 3000 Series, Cisco Systems, Inc. NX-OS 10.2(2) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(3) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(2a) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(3t) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(4) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(5) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(3v) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(6) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(7) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(8) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.2(9) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(1) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(2) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(99w) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3w) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(99x) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3o) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(4a) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3p) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(4) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3q) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3x) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(5) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(4g) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(3r) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(6) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(4h) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(7) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.3(8) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(1) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(2) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(3) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(4) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(5) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(4g) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.4(6) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(1) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(2) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3t) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3e) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3o) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3s) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.5(3p) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.6(1) Nexus 9000 Series, Cisco Systems, Inc. NX-OS 10.6(1s) Nexus 9000 Series",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 Border Gateway Protocol (BGP) \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Cisco NX-OS \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u0438\u0437\u0430\u0442\u043e\u0440\u043e\u0432 Cisco Nexus 3000 Series Switches \u0438 Cisco Nexus 9000 Series Switches, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u0420\u0435\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u044f \u043d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e\u0433\u043e \u043f\u043e\u0442\u043e\u043a\u0430 \u0443\u043f\u0440\u0430\u0432\u043b\u0435\u043d\u0438\u044f (CWE-670)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 Border Gateway Protocol (BGP) \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u043e\u0439 \u0441\u0438\u0441\u0442\u0435\u043c\u044b Cisco NX-OS \u043c\u0430\u0440\u0448\u0440\u0443\u0442\u0438\u0437\u0430\u0442\u043e\u0440\u043e\u0432 Cisco Nexus 3000 Series Switches \u0438 Cisco Nexus 9000 Series Switches \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043e\u0448\u0438\u0431\u043a\u0430\u043c\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 \u0440\u0430\u0437\u0440\u0435\u0448\u0435\u043d\u0438\u0439. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u0430\u043c\u0438",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-bgp-iefab-3hb2pwtx",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-670",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 5,4)\n\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 6,8)"
}

CVE-2026-20171 (GCVE-0-2026-20171)

Vulnerability from cvelistv5 – Published: 2026-05-20 16:06 – Updated: 2026-05-20 18:31

Title

Cisco Nexus 3000 and 9000 Series Border Gateway Protocol Denial of Service Vulnerability

Summary

A vulnerability in the Border Gateway Protocol (BGP) enforce-first-as feature of Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, remote attacker to trigger BGP peer flaps, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect parsing of a transitive BGP attribute. An attacker could exploit this vulnerability by sending a crafted BGP update through an established BGP peer session. If the update propagates to an affected device, it could cause the device to drop the BGP session and flap with the BGP peer that is forwarding this update, resulting in a DoS condition.

Severity

6.8 (Medium)


                        
                          CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-05-20 18:31 UTC

CWE

CWE-670 - Always-Incorrect Control Flow Implementation

Assigner

cisco mitre root Scorecard

References

1 reference

URL	Tags
https://sec.cloudapps.cisco.com/security/center/c…

Impacted products

1 product

Vendor	Product	Version
Cisco	Cisco NX-OS Software	Affected: 10.2(1) Affected: 10.2(1q) Affected: 10.2(2) Affected: 10.2(3) Affected: 10.2(3t) Affected: 10.2(2a) Affected: 10.3(1) Affected: 10.2(4) Affected: 10.3(2) Affected: 10.3(3) Affected: 10.2(5) Affected: 10.2(3v) Affected: 10.4(1) Affected: 10.3(99w) Affected: 10.2(6) Affected: 10.3(3w) Affected: 10.3(99x) Affected: 10.3(3o) Affected: 10.3(4) Affected: 10.3(3p) Affected: 10.3(4a) Affected: 10.4(2) Affected: 10.3(3q) Affected: 10.3(5) Affected: 10.2(7) Affected: 10.4(3) Affected: 10.3(3x) Affected: 10.3(4g) Affected: 10.5(1) Affected: 10.2(8) Affected: 10.3(3r) Affected: 10.3(6) Affected: 10.4(4) Affected: 10.3(4h) Affected: 10.5(2) Affected: 10.3(7) Affected: 10.4(5) Affected: 10.5(3) Affected: 10.2(9) Affected: 10.4(4g) Affected: 10.6(1) Affected: 10.5(3t) Affected: 10.3(8) Affected: 10.4(6) Affected: 10.5(3s) Affected: 10.5(3e) Affected: 10.5(3o) Affected: 10.6(1s) Affected: 10.5(3p)

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20171",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-05-20T18:31:37.215391Z",
                "version": "2.0.3"
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              "type": "ssvc"
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          "dateUpdated": "2026-05-20T18:31:44.204Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
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          "defaultStatus": "unknown",
          "product": "Cisco NX-OS Software",
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          "versions": [
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              "status": "affected",
              "version": "10.2(1)"
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              "status": "affected",
              "version": "10.2(1q)"
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              "version": "10.2(2)"
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              "version": "10.2(3)"
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            {
              "status": "affected",
              "version": "10.2(3t)"
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              "status": "affected",
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            {
              "status": "affected",
              "version": "10.3(2)"
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            {
              "status": "affected",
              "version": "10.3(3)"
            },
            {
              "status": "affected",
              "version": "10.2(5)"
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            {
              "status": "affected",
              "version": "10.2(3v)"
            },
            {
              "status": "affected",
              "version": "10.4(1)"
            },
            {
              "status": "affected",
              "version": "10.3(99w)"
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            {
              "status": "affected",
              "version": "10.2(6)"
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              "status": "affected",
              "version": "10.3(3w)"
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            {
              "status": "affected",
              "version": "10.3(4a)"
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            {
              "status": "affected",
              "version": "10.4(2)"
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            {
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              "version": "10.3(3q)"
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            {
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            {
              "status": "affected",
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            {
              "status": "affected",
              "version": "10.4(3)"
            },
            {
              "status": "affected",
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            {
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              "version": "10.3(4g)"
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              "status": "affected",
              "version": "10.5(1)"
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            {
              "status": "affected",
              "version": "10.2(8)"
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            {
              "status": "affected",
              "version": "10.3(3r)"
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            {
              "status": "affected",
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            {
              "status": "affected",
              "version": "10.4(4)"
            },
            {
              "status": "affected",
              "version": "10.3(4h)"
            },
            {
              "status": "affected",
              "version": "10.5(2)"
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            {
              "status": "affected",
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            {
              "status": "affected",
              "version": "10.4(5)"
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            {
              "status": "affected",
              "version": "10.5(3)"
            },
            {
              "status": "affected",
              "version": "10.2(9)"
            },
            {
              "status": "affected",
              "version": "10.4(4g)"
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            {
              "status": "affected",
              "version": "10.6(1)"
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            {
              "status": "affected",
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            {
              "status": "affected",
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            {
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              "status": "affected",
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            {
              "status": "affected",
              "version": "10.5(3o)"
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            {
              "status": "affected",
              "version": "10.6(1s)"
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              "status": "affected",
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        }
      ],
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        {
          "lang": "en",
          "value": "A vulnerability in the Border Gateway Protocol (BGP)\u0026nbsp;enforce-first-as feature of\u0026nbsp;Cisco Nexus 3000 Series Switches and Cisco Nexus 9000 Series Switches in standalone NX-OS mode could allow an unauthenticated, remote attacker to trigger BGP peer flaps, resulting in a denial of service (DoS) condition.\r\n\r\nThis vulnerability is due to incorrect parsing of a transitive BGP attribute. An attacker could exploit this vulnerability by sending a crafted BGP update through an established BGP peer session. If the update propagates to an affected device, it could cause the device to drop the BGP session and flap with the BGP peer that is forwarding this update, resulting in a DoS condition."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."
        }
      ],
      "metrics": [
        {
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            "attackVector": "NETWORK",
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            "confidentialityImpact": "NONE",
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            "privilegesRequired": "NONE",
            "scope": "CHANGED",
            "userInteraction": "NONE",
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              "description": "Always-Incorrect Control Flow Implementation",
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        }
      ],
      "source": {
        "advisory": "cisco-sa-bgp-iefab-3hb2pwtx",
        "defects": [
          "CSCwr23951"
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        "discovery": "INTERNAL"
      },
      "title": "Cisco Nexus 3000 and 9000 Series Border Gateway Protocol Denial of Service Vulnerability"
    }
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  "cveMetadata": {
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    "dateReserved": "2025-10-08T11:59:15.391Z",
    "dateUpdated": "2026-05-20T18:31:44.204Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

BDU:2026-07293 (CVE-2026-20171)

CVE-2026-20171 (GCVE-0-2026-20171)

Tags

Sightings

Nomenclature

Related by attack behaviour