Low severity · published Apr 14, 2026
CVE-2026-34454
OAuth2 Proxy: Session cookie not cleared when rendering sign-in page
3.5
CVSS
0.2%
EPSS
No
On KEV
Description
OAuth2 Proxy is a reverse proxy that provides authentication using OAuth2 providers. A regression introduced in 7.11.0 prevents OAuth2 Proxy from clearing the session cookie when rendering the sign-in page. In deployments that rely on the sign-in page as part of their logout flow, a user may be shown the sign-in page while the existing session cookie remains valid, meaning the browser session is not actually logged out. On shared workstations 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. This issue is fixed in 7.15.2
CVSS vector
CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Physical
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OA
oauth2-proxy · oauth2-proxy
>= 7.11.0, < 7.15.2 · source: vendor
OP
Oauth2 Proxy · Oauth2 Proxy Project
7.11.0 before 7.15.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34454
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34454
Vendor Advisory
https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.15.2
Release Notes
https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-f24x-5g9q-753f
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8.5
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8.2
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