Description
Traefik 2.11.x before 2.11.58 and 3.x before 3.7.14 contains a race condition in NTLM and Kerberos (Negotiate) backend authentication, where the per-connection sticky round tripper slot is read and written without synchronization. Remote attackers can send concurrent HTTP/2 or HTTP/3 requests over one connection to orphan backend connections, break connection-bound authentication, or crash Traefik.
Affected products
traefik: traefik
References2
- github.com/traefik/traefik/security/advisories/GHSA-mhjw-hmjv-p… Vendor Advisory
- www.vulncheck.com/advisories/traefik-before-2.11.58-and-3.7.14-… Third Party Advisory
Metrics
- CVSS 3.1
-
3.7
LOW
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - CVSS 4.0
-
6.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 17 · as of 8 November 2026
- CWE
- CWE-362
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