High
Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth
Type: advisorySources: OSV
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is an authentication bypass vulnerability in Traefik's ForwardAuth middleware when trustForwardHeader=false is configured and Traefik is deployed behind a trusted upstream proxy. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-35051
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 3 Nov 2026, 12:56 UTC · Revision 1
Source evidence
Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth
core-osv · Original sourcePublished 30 Apr 2026, 20:26 UTC
Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is an authentication bypass vulnerability in Traefik's ForwardAuth middleware when trustForwardHeader=false is configured and Traefik is deployed behind a trusted upstream proxy. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.
osv:CVE-2026-35051
Complete source record
{
"id": "3c73b49a41fc5ec6a64654f363ea923e7d41d024f1df634a242cf3c128711e05",
"url": "https://osv.dev/vulnerability/CVE-2026-35051",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "Traefik: ForwardAuth trustForwardHeader=false allows spoofed X-Forwarded-Prefix to bypass auth",
"summary": "Traefik is an HTTP reverse proxy and load balancer. Prior to versions 2.11.43, 3.6.14, and 3.7.0-rc.2, there is an authentication bypass vulnerability in Traefik's ForwardAuth middleware when trustForwardHeader=false is configured and Traefik is deployed behind a trusted upstream proxy. This issue has been patched in versions 2.11.43, 3.6.14, and 3.7.0-rc.2.",
"evidence": "osv:CVE-2026-35051",
"products": [],
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"aliases": [
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"GHSA-6384-m2mw-rf54",
"GO-2026-5163"
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"database_specific": {
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}
}
],
"modified": "2026-10-28T02:30:28.950216769Z",
"provider": "osv",
"references": [
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"https://github.com/traefik/traefik/releases/tag/v3.6.14",
"https://github.com/traefik/traefik/releases/tag/v3.7.0-rc.2",
"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-35051.json",
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],
"provider_metadata": {
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"cna_assigner": "GitHub_M",
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}
},
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"value": "CVE-2026-35051",
"evidence": "/id"
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"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 495608,
"published_at": "2026-04-30T20:26:06.716+00:00"
}