Answer in brief
CVE-2026-88007 records a Critical severity (CVSS 0.0) vulnerability in Traefik HTTP/3 Backend NTLM Connection Reuse. 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/v2 (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 0.0. 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/v2 (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 | >= 2.11.0, < 2.11.57 || >= 3.0.0, < 3.7.13 | Not reported |
| github.com/traefik/traefikgo | >=0 | Not reported |
| github.com/traefik/traefik/v2go | >=2.11.0,<2.11.57 | 2.11.57 |
| github.com/traefik/traefik/v2go | >=2.11.0 <2.11.57 | 2.11.57 |
| github.com/traefik/traefik/v3go | >=3.0.0 <3.7.13 | 3.7.13 |
| github.com/traefik/traefik/v3go | >=3.0.0,<3.7.13 | 3.7.13 |
Published upstream
Sep 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 10, 2026
Traefik is an open source HTTP reverse proxy and load balancer. From 2.11.0 until 2.11.57 and 3.7.13, the HTTP/3 entrypoint ConnContext does not call service.AddTransportOnContext, so kerberosRoundTripper uses a shared backend transport instead of a transport dedicated to each frontend connection. With HTTP/3 enabled, a backend using connection-bound NTLM or Negotiate authentication, and backend keep-alive, an unrelated client can reuse a backend connection authenticated for a victim, read victim-only data, and act as that victim without the victim credentials. This issue is fixed in 2.11.57 and 3.7.13.
Quoted source text, attributed separately from HOL analysis.