OAuth2 Proxy's session cookies are not cleared when rendering sign-in page

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-34454: 0.18% estimated exploitation activity in the next 30 days; percentile 7.91 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact A regression introduced in v7.11.0 is preventing OAuth2 Proxy from clearing the session cookie when rendering the sign-in page. This only impacts deployments that rely on the sign-in page as part of their logout flow. In those setups, a user may be shown the sign-in page while the existing session cookie remains valid, so the browser session is not actually logged out. On shared workstations be it browsers or devices, a subsequent user could continue to use the previous user's authenticated session. Deployments that use a dedicated logout/sign-out endpoint to terminate sessions are not affected. Patches This issue is fixed in v7.15.2. Workarounds Do not rely on the sign-in page to clear an existing session. Instead: - Use the dedicated logout/sign-out endpoint of OAuth2 Proxy - Ensure your application logout flow explicitly clears the OAuth2 Proxy session cookie before redirecting users to the sign-in page - If needed, clear the session cookie at the reverse proxy or…

Published by the source

14 Apr 2026, 22:31 UTC

Last modified by the source

15 Apr 2026, 21:06 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-f24x-5g9q-753f

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# Patch Next advisory brief: CVE-2026-34454

Advisory: OAuth2 Proxy's session cookies are not cleared when rendering sign-in page
IDs: CVE-2026-34454, GHSA-f24x-5g9q-753f
Record: https://patchnext.com/advisories/cve-2026-34454 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Low (CVSS 3.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/oauth2-proxy/oauth2-proxy/v7 7.15.2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/oauth2-proxy/oauth2-proxy/v7: affected >= 7.11.0, < 7.15.2; fixed in 7.15.2

## Suggested inspection (read-only)
- Go github.com/oauth2-proxy/oauth2-proxy/v7: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/oauth2-proxy/oauth2-proxy/v7.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-f24x-5g9q-753f (GitHub-reviewed advisory GHSA-f24x-5g9q-753f lists affected ranges: Go github.com/oauth2-proxy/oauth2-proxy/v7 >=7.11.0 <7.15.2)

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