CVE-2026-41263: traefik · Timing Side Channel
Affects traefikSource GCVE Database
Not known to be exploited · CVSS 6.3 Medium · fixed in 3.7.0-rc.2 : update traefik when convenient.
Data as of 27 Oct 2026, 00:39 UTC
- Patch
- Available – fixed in 3.7.0-rc.2, 3.6.14, 2.11.43
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 30 Apr 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade traefik to 3.7.0-rc.2, 3.6.14 or 2.11.43.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| traefik traefik | Affected
| Fixed in
|
AI-suggested
Upgrade Traefik to version 2.11.43, 3.6.14, or 3.7.0-rc.2 or later to apply the official fix for this timing side-channel vulnerability. No other mitigation is required as the issue is resolved in these versions.
Description
A timing side-channel vulnerability in Traefik's BasicAuth middleware prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2 allows attackers to enumerate valid usernames by measuring authentication response times. The issue arises because a variable intended for a constant-time fallback secret is empty, causing the comparison to short-circuit quickly and reveal timing differences. This vulnerability has been patched in the specified versions.