CVE-2026-114641 traefik CVE debrief

Who should care

Defenders responsible for Traefik deployments should assess exposure and prioritize patching to prevent exploitation of this vulnerability. This includes operators managing Traefik instances, platform administrators, vulnerability management teams, and security teams responsible for monitoring and mitigating potential threats.

Why it matters

CVE-2026-114641 is a race condition vulnerability in Traefik's NTLM and Kerberos (Negotiate) backend authentication. Defenders responsible for Traefik deployments should assess exposure and prioritize patching to prevent exploitation of this vulnerability.

• Verify Traefik versions to determine if exposure exists.
• Apply patches to prevent exploitation of this vulnerability.
• Monitor Traefik logs for suspicious activity.
• Implement additional security measures to prevent similar vulnerabilities.

Technical summary

The vulnerability is caused by a race condition in the per-connection sticky round tripper slot, which is read and written without synchronization. This allows remote attackers to send concurrent HTTP/2 or HTTP/3 requests over one connection to orphan backend connections, break connection-bound authentication, or crash Traefik. Affected Traefik deployments should assess exposure and prioritize patching to prevent exploitation of this vulnerability. Defenders should verify Traefik versions to determine if exposure exists and apply patches to prevent exploitation.

Defensive priority

Defenders should prioritize verifying Traefik versions and applying patches to prevent exploitation of this vulnerability.

Recommended defensive actions

• Verify Traefik versions and apply patches to prevent exploitation of this vulnerability.
• Monitor Traefik logs for suspicious activity.
• Implement additional security measures to prevent similar vulnerabilities.
• Review compensating controls for exposed systems while remediation is scheduled and verified.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The vulnerability is caused by a race condition in the per-connection sticky round tripper slot, which is read and written without synchronization. This allows remote attackers to send concurrent HTTP/2 or HTTP/3 requests over one connection to orphan backend connections, break connection-bound authentication, or crash Traefik.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.