Traefik from 3.2.0 before 3.7.15 contains a data race in the experimental FastProxy that allows unauthenticated attackers to crash the process by abusing HTTP/1 protocol upgrades. Attackers can repeatedly open and abort upgraded connections such as WebSocket, corrupting the unsynchronized shared bufio.Reader and triggering an unrecovered panic that terminates Traefik.
History

Fri, 30 Oct 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 30 Oct 2026 13:30:00 +0000

Type Values Removed Values Added
Description Traefik from 3.2.0 before 3.7.15 contains a data race in the experimental FastProxy that allows unauthenticated attackers to crash the process by abusing HTTP/1 protocol upgrades. Attackers can repeatedly open and abort upgraded connections such as WebSocket, corrupting the unsynchronized shared bufio.Reader and triggering an unrecovered panic that terminates Traefik.
Title Traefik 3.2.0 before 3.7.15 FastProxy Data Race Denial of Service
First Time appeared Traefik
Traefik traefik
Weaknesses CWE-567
CPEs cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*
Vendors & Products Traefik
Traefik traefik
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

cvssV4_0

{'score': 8.2, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published: 2026-10-30T13:18:12.970Z

Updated: 2026-10-30T15:17:13.625Z

Reserved: 2026-10-30T10:56:15.489Z

Link: CVE-2026-119574

cve-icon Vulnrichment

Updated: 2026-10-30T15:17:09.339Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-30T14:16:46.453

Modified: 2026-10-30T16:17:47.143

Link: CVE-2026-119574

cve-icon Redhat

No data.