CVE-2025-66491

Name
CVE-2025-66491
Description
Traefik is an HTTP reverse proxy and load balancer. Versions 3.5.0 through 3.6.2 have inverted TLS verification logic in the nginx.ingress.kubernetes.io/proxy-ssl-verify annotation. Setting the annotation to "on" (intending to enable backend TLS certificate verification) actually disables verification, allowing man-in-the-middle attacks against HTTPS backends when operators believe they are protected. This issue is fixed in version 3.6.3.
NVD Severity
unknown
Other trackers
CVE, NVD, CERT, CVE Details, CIRCL, Arch Linux, Debian, Red Hat, Ubuntu, Gentoo, SUSE (Bugzilla), SUSE (CVE), Mageia
Mailing lists
oss-security, full-disclosure, bugtraq
Exploits
Exploit DB, Metasploit
Forges
GitHub (code, issues), Aports (code, issues)

References

Type URI
MISC https://github.com/traefik/traefik/commit/14a1aedf5704673d875d210d7bacf103a43c77e4
MISC https://github.com/traefik/traefik/releases/tag/v3.6.3
CONFIRM https://github.com/traefik/traefik/security/advisories/GHSA-7vww-mvcr-x6vj

Match rules

CPE URI Source package Min version Max version
traefik >= 3.5.0 < 3.6.3

Vulnerable and fixed packages

Source package Branch Version Maintainer Status
traefik edge-community 3.6.2-r1 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik edge-community 3.6.2-r0 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik edge-community 3.5.0-r2 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik edge-community 3.5.0-r1 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik edge-community 3.5.0-r0 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r6 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r5 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r4 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r3 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r2 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable
traefik 3.23-community 3.6.2-r1 Francesco Colista <fcolista@alpinelinux.org> possibly vulnerable