{"id":"BIT-oauth2-proxy-2026-34457","summary":"OAuth2 Proxy: Health Check User-Agent Matching Bypasses Authentication in auth_request Mode","details":"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 integration (such as nginx auth_request) and either --ping-user-agent is set or --gcp-healthchecks is enabled. In affected configurations, OAuth2 Proxy treats any request with the configured health check User-Agent value as a successful health check regardless of the requested path, allowing an unauthenticated remote attacker to bypass authentication and access protected upstream resources. Deployments that do not use auth_request-style subrequests or that do not enable --ping-user-agent/--gcp-healthchecks are not affected. This issue is fixed in 7.15.2.","aliases":["CVE-2026-34457","GHSA-5hvv-m4w4-gf6v"],"modified":"2026-04-17T04:57:11.352797722Z","published":"2026-04-16T23:45:31.699Z","database_specific":{"cpes":["cpe:2.3:a:oauth2_proxy_project:oauth2_proxy:*:*:*:*:*:go:*:*"],"severity":"Critical"},"references":[{"type":"WEB","url":"https://github.com/oauth2-proxy/oauth2-proxy/releases/tag/v7.15.2"},{"type":"WEB","url":"https://github.com/oauth2-proxy/oauth2-proxy/security/advisories/GHSA-5hvv-m4w4-gf6v"},{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-34457"}],"affected":[{"package":{"name":"oauth2-proxy","ecosystem":"Bitnami","purl":"pkg:bitnami/oauth2-proxy"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"7.15.2"}]}],"database_specific":{"source":"https://github.com/bitnami/vulndb/tree/main/data/oauth2-proxy/BIT-oauth2-proxy-2026-34457.json"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}],"schema_version":"1.7.5"}