Authlib: is_secure_transport() loopback exemption can be bypassed with a userinfo component, allowing cleartext-HTTP URLs to non-loopback hosts

影響: pip:authlib <= 1.7.2 → 1.8.0

authlib.common.security.is_secure_transport() is used throughout Authlib to enforce the OAuth 2.0 / OIDC requirement that endpoint and redirect URIs use TLS, with an RFC 8252 §7.3 exemption for loopback http:// URIs. The check is implemented as a textual str.startswith prefix match, so a URL such as http://localhost:80@evil.example/cb — whose actual host is evil.example and whose scheme is plain http — is accepted as "secure". An attacker who can supply a URL to any of the sinks that rely on th…

在 GitHub Advisory Database 阅读

2026/10/28 00:37，GitHub Advisory Database 发布了“Authlib: is_secure_transport() loopback exemption can be bypassed with a userinfo component, allowing cleartext-HTTP URLs to non-loopback hosts”（类型：漏洞公告）。严重程度为“低危”（low）。相关技术：Python。CVE：CVE-2026-114614。