High severity · published Aug 6, 2026
CVE-2026-71327
Traefik: Gateway API route identity collision allows cross-namespace backend hijacking
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
Traefik is an open source HTTP reverse proxy and load balancer. From 3.0.0 until 3.6.25 and 3.7.10, Traefik's Kubernetes Gateway API provider in pkg/provider/kubernetes/gateway/httproute.go, grpcroute.go, tcproute.go, and tlsroute.go builds HTTPRoute, GRPCRoute, TCPRoute, and TLSRoute router and service identities by hyphen-concatenating namespace, route name, Gateway identity, entry point, and rule index, allowing colliding Routes to overwrite another namespace's backend. This issue is fixed in 3.6.25 and 3.7.10.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TR
traefik · traefik
>= 3.0.0, < 3.6.25; >= 3.7.0, < 3.7.10 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-71327
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-71327
Patch
https://github.com/traefik/traefik/commit/a764166656f0cd337f917ac76315c381cca844f9
Issue Tracking
https://github.com/traefik/traefik/pull/13580
Patch
https://github.com/traefik/traefik/releases/tag/v3.6.25
Patch
https://github.com/traefik/traefik/releases/tag/v3.7.10
Patch
https://github.com/traefik/traefik/security/advisories/GHSA-fgjj-px3w-67xx
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