CVE-2025-55162: envoyproxy envoy · Insufficient Session Expiration
Affects envoyproxy envoySource CVE Database V5
Not known to be exploited · CVSS 6.3 Medium · fixed in 1.32.10 : update envoyproxy envoy when convenient.
Data as of 26 Oct 2026, 11:42 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 27% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.32.10
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:L/A:NExploitation evidence
Disclosed: evidence found.
CVE published 3 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
European organizations should immediately audit their Envoy deployments to identify affected versions. Upgrading to the fixed versions (1.32.10, 1.33.7, 1.34.5, or 1.35.1) is the primary and most effective mitigation. Where immediate upgrade is not feasible, organizations should consider the following additional measures: 1) Review and adjust OAuth2 filter cookie configurations to avoid using __Secure- or __Host- prefixed cookie names until patched versions are deployed. 2) Implement additional session management controls such as server-side session invalidation and short session lifetimes to reduce the window of exposure. 3) Enforce multi-factor authentication (MFA) to mitigate unauthorized access even if session hijacking occurs. 4) Monitor logs for anomalous session activity indicative of hijacking attempts. 5) Educate users about the risks of shared device usage and encourage explicit browser session termination or use of private browsing modes. 6) Deploy web application firewalls (WAFs) or proxy rules to detect and block suspicious session reuse patterns. These targeted mitigations complement patching and help reduce risk in the interim.
Description
Envoy is an open source L7 proxy and communication bus designed for large modern service oriented architectures. In versions below 1.32.10 and 1.33.0 through 1.33.6, 1.34.0 through 1.34.4 and 1.35.0, insufficient Session Expiration in the Envoy OAuth2 filter leads to failed logout operations. When configured with __Secure- or __Host- prefixed cookie names, the filter fails to append the required Secure attribute to the Set-Cookie header during deletion. Modern browsers ignore this invalid request, causing the session cookie to persist. This allows a user to remain logged in after they believe they have logged out, creating a session hijacking risk on shared computers. The current implementation iterates through the configured cookie names to generate deletion headers but does not check for these prefixes. This failure to properly construct the deletion header means the user's session cookies are never removed by the browser, leaving the session active and allowing the next user of the same browser to gain unauthorized access to the original user's account and data. This is fixed in versions 1.32.10, 1.33.7, 1.34.5 and 1.35.1.