Answer in brief
CVE-2026-53622 records a High severity (CVSS 10.0) vulnerability in Traefik: HTTP/3 mTLS bypass via exact SNI TLSOptions lookup for wildcard and mixed-case hosts. The current sources do not mark it as known exploited. The current feed maps traefik/traefik (generic), github.com/traefik/traefik (go), github.com/traefik/traefik (go), github.com/traefik/traefik/v2 (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 10.0. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps traefik/traefik (generic), github.com/traefik/traefik (go), github.com/traefik/traefik (go), github.com/traefik/traefik/v2 (go) and additional mapped packages. Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| traefik/traefikgeneric | >= 3.7.0, < 3.7.3 || >= 3.0.0, < 3.6.18 || < 2.11.51 | Not reported |
| github.com/traefik/traefikgo | <=1.7.34 | Not reported |
| github.com/traefik/traefikgo | >=0 | Not reported |
| github.com/traefik/traefik/v2go | >=0 <2.11.51 | 2.11.51 |
| github.com/traefik/traefik/v2go | >=0 | Not reported |
| github.com/traefik/traefik/v2go | <=2.11.50 | 2.11.51 |
| github.com/traefik/traefik/v3go | >=3.7.0,<=3.7.2 | 3.7.3 |
| github.com/traefik/traefik/v3go | <=3.6.17 | 3.6.18 |
| github.com/traefik/traefik/v3go | >=0 <3.7.3 | 3.7.3 |
| github.com/traefik/traefik/v3go | >=3.7.0 <3.7.3 | 3.7.3 |
| github.com/traefik/traefik/v3go | >=0 <3.6.18 | 3.6.18 |
| Traefikgo | >=0 <3.7.3 | 3.7.3 |
| Traefikgo | <=3.7.2 | 3.7.3 |
Published upstream
Jun 23, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 19, 2026
Traefik is an HTTP reverse proxy and load balancer. Versions prior to 3.7.3, 3.6.18, and 2.11.51 have a critical vulnerability in Traefik's HTTP/3 (QUIC) TLS configuration selection that allows unauthenticated clients to bypass router-specific mTLS enforcement. When HTTP/3 is enabled on an entrypoint, the TLS handshake selects the applicable TLS configuration through an exact, case-sensitive lookup on the SNI value, which fails to match wildcard host patterns (e.g., *.example.com) or case variants of the configured hostname. Because the handshake falls back to the default TLS configuration — which may not require client certificates — a client can complete the QUIC handshake without presenting a certificate, while the subsequent HTTP routing layer still dispatches the request to a backend protected by a router-specific mTLS policy. The issue affects deployments where HTTP/3 is enabled, a router uses a wildcard Host rule or case-insensitive hostname matching, a router-specific TLSOptions enforces client certificate authentication, and UDP access to the entrypoint is reachable by an attacker. This vulnerability is fixed in versions 3.7.3, 3.6.18, and 2.11.51.
Quoted source text, attributed separately from HOL analysis.