# CVE-2026-34454: OAuth2 Proxy insufficient session expiration in sign-in page handler

Source: https://junglewise.ai/threats/cve-2026-34454-oauth2-proxy-insufficient-session-expiration-in-sign-in-page  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-14. Updated: 2026-07-25  
License: CC BY 4.0 with a link back

CVE-2026-34454 · Severity: low · CVSS 3.5 · Published 2026-04-14

OAuth2 Proxy is a tool used to manage user logins for web applications. A bug in certain versions prevents the software from properly clearing a user's session cookie when they are sent to the sign-in page. On shared computers, this could allow a new user to access the previous person's account because the session was never actually terminated.

Technologies: [github.com/oauth2-proxy/oauth2-proxy (Go)](https://junglewise.ai/threats/technologies/github-com-oauth2-proxy-oauth2-proxy), [github.com/oauth2-proxy/oauth2-proxy/v7 (Go)](https://junglewise.ai/threats/technologies/github-com-oauth2-proxy-oauth2-proxy-v7), [OAuth2 Proxy](https://junglewise.ai/threats/technologies/oauth2-proxy). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [OAuth2 Proxy](https://junglewise.ai/threats/vendors/oauth2-proxy).

## Quick answers

**Is CVE-2026-34454 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-34454 being exploited in the wild.

**How severe is CVE-2026-34454?** Low severity, with a CVSS score of 3.5, published 14 April 2026.

**Which products and versions are affected?** github.com/oauth2-proxy/oauth2-proxy (Go) SEMVER:introduced=0; github.com/oauth2-proxy/oauth2-proxy/v7 (Go) >= 7.11.0, < 7.15.2, SEMVER:introduced=7.11.0,fixed=7.15.2; OAuth2 Proxy >= 7.11.0, < 7.15.2.

**Is there a fix for CVE-2026-34454?** Yes. github.com/oauth2-proxy/oauth2-proxy/v7 (Go): upgrade to 7.15.2 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-34454 attacked?** It is attacked with physical access, in a software library.

**Am I affected by CVE-2026-34454?** Check whether you run github.com/oauth2-proxy/oauth2-proxy (Go), github.com/oauth2-proxy/oauth2-proxy/v7 (Go) or OAuth2 Proxy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/oauth2-proxy/oauth2-proxy/v7 (Go): upgrade to 7.15.2 or later

  ```sh
  go get github.com/oauth2-proxy/oauth2-proxy/v7@v7.15.2
  ```


## Technical details

A regression in OAuth2 Proxy (v7.11.0 to v7.15.1) prevents the sign-in page handler from clearing existing session cookies. In environments where the sign-in page is used as a component of the logout flow, the browser may retain a valid session cookie even after the user believes they have logged out. This is classified as insufficient session expiration (CWE-613) and session fixation (CWE-384). An attacker with physical access to a shared workstation can resume the previous user's authenticated session. The issue is resolved in version 7.15.2 by ensuring the session cookie is cleared at the beginning of the sign-in page handler.

## Affected products

- OAuth2 Proxy Project OAuth2 Proxy >= 7.11.0, < 7.15.2

## Identifiers

- CVE-2026-34454
- GHSA-f24x-5g9q-753f
- GO-2026-5341

## Timeline

- 2026-04-14: disclosed
- 2026-04-14: patched: Fixed in version 7.15.2
- 2026-04-14: advisory

## References

- [https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.15.2](https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.15.2)
- [https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-f24x-5g9q-753f](https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-f24x-5g9q-753f)

## Related threats

- [OAuth2 Proxy authentication bypass via spoofed X-Forwarded-Uri header](https://junglewise.ai/threats/cve-2026-76835-oauth2-proxy-authentication-bypass-via-spoofed-x-forwarded-uri)
- [OAuth2 Proxy has an Authentication Bypass via Fragment Confusion in skip_auth_routes and skip_auth_regex](https://junglewise.ai/threats/cve-2026-41059-oauth2-proxy-has-an-authentication-bypass-via-fragment-confusion)
- [OAuth2 Proxy authentication bypass via X-Forwarded-Uri spoofing](https://junglewise.ai/threats/cve-2026-40575-oauth2-proxy-authentication-bypass-via-x-forwarded-uri-spoofing)
- [OAuth2 Proxy has an Authorization Bypass in Email Domain Validation via Malformed Multi-@ Email Claims](https://junglewise.ai/threats/cve-2026-40574-oauth2-proxy-has-an-authorization-bypass-in-email-domain)
- [OAuth2 Proxy authentication bypass via health check User-Agent spoofing](https://junglewise.ai/threats/cve-2026-34457-oauth2-proxy-authentication-bypass-via-health-check-user-agent)