CVE-2026-119574

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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/traefik/traefik/security/advisories/GHSA-ww7c-q3mv-xx22
https://www.vulncheck.com/advisories/traefik-3.2.0-before-3.7.15-fastproxy-data-race-denial-of-service

Configurations

No configuration.

History

30 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 14:16

Updated : 2026-10-30 16:17

NVD link : CVE-2026-119574

Mitre link : CVE-2026-119574

CVE.ORG link : CVE-2026-119574

JSON object : View

Products Affected

No product.

CWE

CWE-567

Unsynchronized Access to Shared Data in a Multithreaded Context

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