What is CVE-2026-34457?

CVE-2026-34457 is a critical-severity vulnerability in Oauth2-proxy, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-04-14.

How severe is CVE-2026-34457?

Critical severity. CVSS v3 base score is 9.1 out of 10.

Vulnerability in Oauth2-proxy

CVE-2026-34457

OAuth2 Proxy is a reverse proxy that provides authentication using OAuth2 providers. Versions prior to 7.15.2 contain a configuration-dependent authentication bypass in deployments where OAuth2 Proxy is used with an auth_request-style inte…

EPSS: 0.001 (17.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.

Affected products

Oauth2-proxy — versions < 7.15.2

Weakness classification (CWE)

CWE-290 — Authentication Bypass by Spoofing

References

https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-5hvv-m4w4-gf6v (x_refsource_CONFIRM)
https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.15.2 (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-34457?: CVE-2026-34457 is a critical-severity vulnerability in Oauth2-proxy, classified under Authentication Bypass by Spoofing. CVSS score: 9.1/10. Published 2026-04-14.
How severe is CVE-2026-34457?: Critical severity. CVSS v3 base score is 9.1 out of 10.