CVE-2025-26399 (GCVE-0-2025-26399)

Vulnerability from cvelistv5 – Published: 2025-09-23 05:07 – Updated: 2026-08-04 03:55
VLAI CISA Previdian
Title
SolarWinds Web Help Desk Deserialization of Untrusted Data Privilege Escalation Vulnerability
Summary
SolarWinds Web Help Desk was found to be susceptible to an unauthenticated AjaxProxy deserialization remote code execution vulnerability that, if exploited, would allow an attacker to run commands on the host machine. This vulnerability is a patch bypass of CVE-2024-28988, which in turn is a patch bypass of CVE-2024-28986.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: active Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-09-23 00:00 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
References
Impacted products
Vendor Product Version
SolarWinds Web Help Desk Affected: 12.8.7 and below
Create a notification for this product.
Credits
Anonymous working with Trend Micro Zero Day Initiative
CISA
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 69cea37a-e33b-4574-8a56-40865d3636f4

Vulnerability ID: CVE-2025-26399

Status: Confirmed

Status Updated: 2026-03-09 01:00 CET

Exploited: Yes

Timestamps
First Seen: 2026-03-09
Asserted: 2026-03-09
Scope
Notes: SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability | Affected: SolarWinds / Web Help Desk | Description: SolarWinds Web Help Desk contain a deserialization of untrusted data vulnerability in AjaxProxy that could allow an attacker to run commands on the host machine. | Required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. | Due date: 2026-03-12 | Known ransomware campaign use (KEV): Known | Notes (KEV): https://www.solarwinds.com/trust-center/security-advisories/cve-2025-26399 ; https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm ; https://nvd.nist.gov/vuln/detail/CVE-2025-26399
Evidence

Type: Vendor Report

Signal: Successful Exploitation

Confidence: 80%

Source: cisa-kev

Details
Cwes CWE-502
Feed CISA Known Exploited Vulnerabilities Catalog
Product Web Help Desk
Due Date 2026-03-12
Date Added 2026-03-09
Vendorproject SolarWinds
Vulnerabilityname SolarWinds Web Help Desk Deserialization of Untrusted Data Vulnerability
Knownransomwarecampaignuse Known
References
Created: 2026-10-02 08:09 CEST | Updated: 2026-10-02 08:09 CEST
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
KEV entry ID: 183c8f01-3593-4a48-b2c2-4556f96ce950

Vulnerability ID: CVE-2025-26399

Status: Confirmed

Status Updated: 2026-06-01 14:09 CEST

Exploited: Yes

Timestamps
First Seen: 2026-06-01
Asserted: 2026-06-01
Scope
Notes: SolarWinds Web Help Desk Deserialization of Untrusted Data Privilege Escalation Vulnerability | Affected: SolarWinds / Web Help Desk | CVSS: 9.8 (CRITICAL) | EPSS: 0.895 | Used in malware: unknown | Listed 1 day ahead of CISA KEV | Not yet in CISA KEV: False
Evidence

Type: Public Report

Signal: Successful Exploitation

Confidence: 70%

Source: previdian

Details
Feed Previdian (previdian.com)
Title SolarWinds Web Help Desk Deserialization of Untrusted Data Privilege Escalation Vulnerability
Cve Id CVE-2025-26399
Vendor SolarWinds
Ghsa Id GHSA-VFRJ-F292-3F24
Product Web Help Desk
Added Date 2026-06-01T12:09:49.246Z
Cvss Score 9.8
Epss Score 0.895
Previous Ids
Cvss Severity CRITICAL
Virtual Patch False
Cvss Estimated False
Epss Percentile 0.99783
Used In Malware unknown
Vulnerability Id CVE-2025-26399
Ahead Of Cisa Kev 
{
  "count": 1,
  "unit": "day"
}
Not Yet In Cisa Kev False
References
Created: 2026-10-02 09:09 CEST | Updated: 2026-10-02 09:09 CEST
Show details on NVD website
To clipboard 

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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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.



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.