CVE-2025-66490
Fixed in a distro release EPSS <1%CVSS 6.9
Traefik is an HTTP reverse proxy and load balancer. For versions prior to 2.11.32 and 2.11.31 through 3.6.2, requests using PathPrefix, Path or PathRegex matchers can bypass path normalization. When Traefik uses path-based routing, requests containing URL-encoded restricted characters (/, \, Null, ;, ?, #) can bypass the middleware chain and reach unintended backends. For example, a request to http://mydomain.example.com/admin%2F could reach service-a without triggering my-security-middleware, bypassing security controls for the /admin/ path. This issue is fixed in versions 2.11.32 and 3.6.3.
Products: traefik
Fixed upstream
| Ecosystem | Package | Fixed in |
|---|---|---|
| Go | github.com/traefik/traefik | no fix |
| Go | github.com/traefik/traefik/v2 | 2.11.32 |
| Go | github.com/traefik/traefik/v3 | 3.6.3 |
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Chainguard | traefik-3.4 | no fix |
| Chainguard | traefik-3.5 | no fix |
| Chainguard | traefik-3.5 | 3.5.6-r6 |
| Chainguard | traefik-fips-3.5 | no fix |
| Wolfi | traefik-3.4 | no fix |
| Wolfi | traefik-3.5 | 3.5.6-r6 |
| openSUSE Leap 15.6 | govulncheck-vulndb | 0.0.20251230T014957-150000.1.134.1 |
| openSUSE Leap 16.0 | govulncheck-vulndb | 0.0.20260723T184607-160000.1.1 |
| openSUSE Tumbleweed | traefik | 3.6.6-1.1 |
| openSUSE Tumbleweed | traefik2 | 2.11.35-1.1 |