Description
Traefik versions before v2.11.55 and versions v3.0.0 through v3.7.10 contain an authentication bypass vulnerability in the digestAuth middleware where unknown usernames receive an empty secret instead of rejection. Attackers can compute a valid digest response using the empty secret and arbitrary credentials to bypass authentication on any digestAuth-protected route without a valid username or password.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| traefik | traefik | < 2.11.55, 3.0.0 – ≤ 3.7.10 | 2.11.55 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | traefik-3.6 | No fix yet | — |
Public exploits
Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.
GitHub 1 repository
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Boreas37/CVE-2026-85595-PoC ★ 0 · Oct 25, 2026
CVE-2026-85595 — Traefik digestAuth authentication bypass (unknown username => empty HA1). Lab-verified: v3.7.10 bypass, v3.7.11 401.
Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Traefik < 2.11.55 / 3.0.0 - 3.7.10 - Digest Authentication Bypass http/cves/2026/CVE-2026-85595.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
References
- GitHub Security Advisory (GHSA-5w68-77r2-r64c) vendor-advisory
- VulnCheck Advisory: Traefik before v2.11.55 Authentication Bypass via digestAuth third-party-advisory