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EUVD-2026-274638

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:03

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:03:49.725832+00:00",
  "id": "EUVD-2026-274638"
}

CVE-2026-20009 (GCVE-0-2026-20009)

Vulnerability from cvelistv5 – Published: 2026-03-04 17:06 – Updated: 2026-03-05 15:49

Title

Cisco Secure Firewall Adaptive Security Appliance SSH Partial Private Key Authentication Bypass Vulnerability

Summary

A vulnerability in the implementation of the proprietary SSH stack with SSH key-based authentication in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to log in to a Cisco Secure Firewall ASA device and execute commands as a specific user. This vulnerability is due to insufficient validation of user input during the SSH authentication phase. An attacker could exploit this vulnerability by submitting crafted input during SSH authentication to an affected device. A successful exploit could allow the attacker to log in to the device as a specific user without the private SSH key of that user. To exploit this vulnerability, the attacker must possess a valid username and the associated public key. The private key is not required. Notes: Exploitation of this vulnerability does not provide the attacker with root access. The authentication, authorization, and accounting (AAA) configuration command auto-enable is not affected by this vulnerability.

Severity

5.3 (Medium)


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

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-05 15:49 UTC

CWE

CWE-138 - Improper Neutralization of Special Elements

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 Secure Firewall Adaptive Security Appliance (ASA) Software	Affected: 9.17.1 Affected: 9.17.1.7 Affected: 9.17.1.9 Affected: 9.17.1.10 Affected: 9.18.1 Affected: 9.18.1.3 Affected: 9.17.1.11 Affected: 9.18.2 Affected: 9.17.1.13 Affected: 9.17.1.15 Affected: 9.18.2.5 Affected: 9.17.1.20 Affected: 9.18.2.7 Affected: 9.19.1 Affected: 9.18.2.8 Affected: 9.18.3 Affected: 9.19.1.5 Affected: 9.17.1.30 Affected: 9.19.1.9 Affected: 9.18.3.39 Affected: 9.19.1.12 Affected: 9.18.3.46 Affected: 9.19.1.18 Affected: 9.18.3.53 Affected: 9.18.3.55 Affected: 9.17.1.33 Affected: 9.18.3.56 Affected: 9.20.1 Affected: 9.19.1.22 Affected: 9.18.4 Affected: 9.20.1.5 Affected: 9.18.4.5 Affected: 9.19.1.24 Affected: 9.18.4.8 Affected: 9.20.2 Affected: 9.19.1.27 Affected: 9.18.4.22 Affected: 9.20.2.10 Affected: 9.19.1.28 Affected: 9.17.1.39 Affected: 9.18.4.24 Affected: 9.20.2.21 Affected: 9.19.1.31 Affected: 9.18.4.29 Affected: 9.20.2.22 Affected: 9.18.4.34 Affected: 9.20.3 Affected: 9.18.4.40 Affected: 9.23.1 Affected: 9.22.1.1 Affected: 9.20.3.4 Affected: 9.18.4.47 Affected: 9.20.3.7 Affected: 9.17.1.45 Affected: 9.19.1.37 Affected: 9.17.1.46 Affected: 9.20.3.9 Affected: 9.19.1.38 Affected: 9.18.4.50 Affected: 9.22.1.3 Affected: 9.20.3.10 Affected: 9.22.1.2 Affected: 9.18.4.52 Affected: 9.20.3.13 Affected: 9.22.1.6 Affected: 9.18.4.53 Affected: 9.22.2 Affected: 9.20.3.16 Affected: 9.19.1.42 Affected: 9.18.4.57 Affected: 9.23.1.3 Affected: 9.20.3.20 Affected: 9.22.2.4 Affected: 9.23.1.7 Affected: 9.20.4 Affected: 9.22.2.9 Affected: 9.23.1.13 Affected: 9.20.4.7 Affected: 9.22.2.13 Affected: 9.18.4.66 Affected: 9.18.4.67 Affected: 9.18.4.68

Show details on NVD website

JSON

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{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20009",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-05T15:49:23.840271Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-03-05T15:49:42.424Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Cisco Secure Firewall Adaptive Security Appliance (ASA) Software",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "9.17.1"
            },
            {
              "status": "affected",
              "version": "9.17.1.7"
            },
            {
              "status": "affected",
              "version": "9.17.1.9"
            },
            {
              "status": "affected",
              "version": "9.17.1.10"
            },
            {
              "status": "affected",
              "version": "9.18.1"
            },
            {
              "status": "affected",
              "version": "9.18.1.3"
            },
            {
              "status": "affected",
              "version": "9.17.1.11"
            },
            {
              "status": "affected",
              "version": "9.18.2"
            },
            {
              "status": "affected",
              "version": "9.17.1.13"
            },
            {
              "status": "affected",
              "version": "9.17.1.15"
            },
            {
              "status": "affected",
              "version": "9.18.2.5"
            },
            {
              "status": "affected",
              "version": "9.17.1.20"
            },
            {
              "status": "affected",
              "version": "9.18.2.7"
            },
            {
              "status": "affected",
              "version": "9.19.1"
            },
            {
              "status": "affected",
              "version": "9.18.2.8"
            },
            {
              "status": "affected",
              "version": "9.18.3"
            },
            {
              "status": "affected",
              "version": "9.19.1.5"
            },
            {
              "status": "affected",
              "version": "9.17.1.30"
            },
            {
              "status": "affected",
              "version": "9.19.1.9"
            },
            {
              "status": "affected",
              "version": "9.18.3.39"
            },
            {
              "status": "affected",
              "version": "9.19.1.12"
            },
            {
              "status": "affected",
              "version": "9.18.3.46"
            },
            {
              "status": "affected",
              "version": "9.19.1.18"
            },
            {
              "status": "affected",
              "version": "9.18.3.53"
            },
            {
              "status": "affected",
              "version": "9.18.3.55"
            },
            {
              "status": "affected",
              "version": "9.17.1.33"
            },
            {
              "status": "affected",
              "version": "9.18.3.56"
            },
            {
              "status": "affected",
              "version": "9.20.1"
            },
            {
              "status": "affected",
              "version": "9.19.1.22"
            },
            {
              "status": "affected",
              "version": "9.18.4"
            },
            {
              "status": "affected",
              "version": "9.20.1.5"
            },
            {
              "status": "affected",
              "version": "9.18.4.5"
            },
            {
              "status": "affected",
              "version": "9.19.1.24"
            },
            {
              "status": "affected",
              "version": "9.18.4.8"
            },
            {
              "status": "affected",
              "version": "9.20.2"
            },
            {
              "status": "affected",
              "version": "9.19.1.27"
            },
            {
              "status": "affected",
              "version": "9.18.4.22"
            },
            {
              "status": "affected",
              "version": "9.20.2.10"
            },
            {
              "status": "affected",
              "version": "9.19.1.28"
            },
            {
              "status": "affected",
              "version": "9.17.1.39"
            },
            {
              "status": "affected",
              "version": "9.18.4.24"
            },
            {
              "status": "affected",
              "version": "9.20.2.21"
            },
            {
              "status": "affected",
              "version": "9.19.1.31"
            },
            {
              "status": "affected",
              "version": "9.18.4.29"
            },
            {
              "status": "affected",
              "version": "9.20.2.22"
            },
            {
              "status": "affected",
              "version": "9.18.4.34"
            },
            {
              "status": "affected",
              "version": "9.20.3"
            },
            {
              "status": "affected",
              "version": "9.18.4.40"
            },
            {
              "status": "affected",
              "version": "9.23.1"
            },
            {
              "status": "affected",
              "version": "9.22.1.1"
            },
            {
              "status": "affected",
              "version": "9.20.3.4"
            },
            {
              "status": "affected",
              "version": "9.18.4.47"
            },
            {
              "status": "affected",
              "version": "9.20.3.7"
            },
            {
              "status": "affected",
              "version": "9.17.1.45"
            },
            {
              "status": "affected",
              "version": "9.19.1.37"
            },
            {
              "status": "affected",
              "version": "9.17.1.46"
            },
            {
              "status": "affected",
              "version": "9.20.3.9"
            },
            {
              "status": "affected",
              "version": "9.19.1.38"
            },
            {
              "status": "affected",
              "version": "9.18.4.50"
            },
            {
              "status": "affected",
              "version": "9.22.1.3"
            },
            {
              "status": "affected",
              "version": "9.20.3.10"
            },
            {
              "status": "affected",
              "version": "9.22.1.2"
            },
            {
              "status": "affected",
              "version": "9.18.4.52"
            },
            {
              "status": "affected",
              "version": "9.20.3.13"
            },
            {
              "status": "affected",
              "version": "9.22.1.6"
            },
            {
              "status": "affected",
              "version": "9.18.4.53"
            },
            {
              "status": "affected",
              "version": "9.22.2"
            },
            {
              "status": "affected",
              "version": "9.20.3.16"
            },
            {
              "status": "affected",
              "version": "9.19.1.42"
            },
            {
              "status": "affected",
              "version": "9.18.4.57"
            },
            {
              "status": "affected",
              "version": "9.23.1.3"
            },
            {
              "status": "affected",
              "version": "9.20.3.20"
            },
            {
              "status": "affected",
              "version": "9.22.2.4"
            },
            {
              "status": "affected",
              "version": "9.23.1.7"
            },
            {
              "status": "affected",
              "version": "9.20.4"
            },
            {
              "status": "affected",
              "version": "9.22.2.9"
            },
            {
              "status": "affected",
              "version": "9.23.1.13"
            },
            {
              "status": "affected",
              "version": "9.20.4.7"
            },
            {
              "status": "affected",
              "version": "9.22.2.13"
            },
            {
              "status": "affected",
              "version": "9.18.4.66"
            },
            {
              "status": "affected",
              "version": "9.18.4.67"
            },
            {
              "status": "affected",
              "version": "9.18.4.68"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A vulnerability in the implementation of the proprietary SSH stack with SSH key-based authentication in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to log in to a Cisco Secure Firewall ASA device and execute commands as a specific user.\r\n\r\nThis vulnerability is due to insufficient validation of user input during the SSH authentication phase. An attacker could exploit this vulnerability by submitting crafted input during SSH authentication to an affected device. A successful exploit could allow the attacker to log in to the device as a specific user without the private SSH key of that user. To exploit this vulnerability, the attacker must possess a valid username and the associated public key. The private key is not required.\r\nNotes:\r\n\r\nExploitation of this vulnerability does not provide the attacker with root access.\r\nThe authentication, authorization, and accounting (AAA) configuration command auto-enable is not affected by this vulnerability.\u0026nbsp;\u0026nbsp;"
        }
      ],
      "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": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "LOW",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N",
            "version": "3.1"
          },
          "format": "cvssV3_1"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-138",
              "description": "Improper Neutralization of Special Elements",
              "lang": "en",
              "type": "cwe"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-04T17:06:58.606Z",
        "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
        "shortName": "cisco"
      },
      "references": [
        {
          "name": "cisco-sa-asa-ssh-keybypass-cr5xPUSf",
          "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-ssh-keybypass-cr5xPUSf"
        }
      ],
      "source": {
        "advisory": "cisco-sa-asa-ssh-keybypass-cr5xPUSf",
        "defects": [
          "CSCwq24081"
        ],
        "discovery": "INTERNAL"
      },
      "title": "Cisco Secure Firewall Adaptive Security Appliance SSH Partial Private Key Authentication Bypass Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
    "assignerShortName": "cisco",
    "cveId": "CVE-2026-20009",
    "datePublished": "2026-03-04T17:06:58.606Z",
    "dateReserved": "2025-10-08T11:59:15.350Z",
    "dateUpdated": "2026-03-05T15:49:42.424Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
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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.

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EUVD-2026-274638

CVE-2026-20009 (GCVE-0-2026-20009)

Tags

Sightings

Nomenclature

Related by attack behaviour