Detections
Analytics

CVE-2025-26399

critical

Description

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.

References

https://www.microsoft.com/en-us/security/blog/2026/02/06/active-exploitation-solarwinds-web-help-desk/

https://www.securityweek.com/hackers-abuse-qemu-for-defense-evasion/

https://securityaffairs.com/190982/security/hidden-vms-how-hackers-leverage-qemu-to-stealthily-steal-data-and-spread-malware.html

https://www.bleepingcomputer.com/news/security/payouts-king-ransomware-uses-qemu-vms-to-bypass-endpoint-security/

https://www.sophos.com/blog/qemu-abused-to-evade-detection-and-enable-ransomware-delivery

https://www.securityweek.com/recent-ivanti-endpoint-manager-flaw-exploited-in-attacks/

https://therecord.media/cisa-shortens-patch-deadline-ivanti-solarwinds

https://thehackernews.com/2026/03/cisa-flags-solarwinds-ivanti-and.html

https://securityaffairs.com/189172/security/u-s-cisa-adds-ivanti-epm-solarwinds-and-omnissa-workspace-one-flaws-to-its-known-exploited-vulnerabilities-catalog.html

https://www.cisa.gov/news-events/alerts/2026/03/09/cisa-adds-three-known-exploited-vulnerabilities-catalog

https://www.bleepingcomputer.com/news/security/threat-actors-exploit-solarwinds-wdh-flaws-to-deploy-velociraptor/

https://www.bleepingcomputer.com/news/security/solarwinds-warns-of-critical-web-help-desk-rce-auth-bypass-flaws/

https://labs.watchtowr.com/buy-a-help-desk-bundle-a-remote-access-solution-solarwinds-web-help-desk-pre-auth-rce-chain-s/

https://thehackernews.com/2026/02/researchers-observe-in-wild.html

https://www.theregister.com/2026/02/09/solarwinds_mystery_whd_attack/

https://www.securityweek.com/recent-solarwinds-flaws-potentially-exploited-as-zero-days/

https://thehackernews.com/2026/02/solarwinds-web-help-desk-exploited-for.html

https://securityaffairs.com/187761/security/attackers-abuse-solarwinds-web-help-desk-to-install-zoho-agents-and-velociraptor.html

https://www.securityweek.com/solarwinds-patches-critical-web-help-desk-vulnerabilities/

https://thehackernews.com/2026/01/solarwinds-fixes-four-critical-web-help.html

https://horizon3.ai/attack-research/cve-2025-40551-another-solarwinds-web-help-desk-deserialization-issue/

https://www.helpnetsecurity.com/2025/09/24/solarwinds-web-help-desk-rce-cve-2025-26399/

https://securityaffairs.com/182545/security/solarwinds-fixed-a-critical-rce-flaw-in-its-web-help-desk-software.html

https://www.theregister.com/2025/09/23/solarwinds_patches_rce/

https://www.securityweek.com/solarwinds-makes-third-attempt-at-patching-exploited-vulnerability/

https://www.bleepingcomputer.com/news/security/solarwinds-releases-third-patch-to-fix-web-help-desk-rce-bug/

https://thehackernews.com/2025/09/solarwinds-releases-hotfix-for-critical.html

https://www.solarwinds.com/trust-center/security-advisories/CVE-2025-26399

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2025-26399

https://documentation.solarwinds.com/en/success_center/whd/content/release_notes/whd_12-8-7-hotfix-1_release_notes.htm

Details

Source: Mitre, NVD

Published: 2025-09-23

Updated: 2026-03-10

Known Exploited Vulnerability (KEV)

Risk Information

CVSS v2

Base Score: 10

Vector: CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C

Severity: Critical

CVSS v3

Base Score: 9.8

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

Severity: Critical

EPSS

EPSS: 0.29278

Vulnerability Watch

Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.

Vulnerability Being Monitored