Traefik is an open source HTTP reverse proxy and load balancer. Prior to 2.11.57, and 3.7.13, Traefik accepts a rootless HTTP/1 request target that Go stores in URL.Opaque while leaving URL.Path empty. The rewriteRequestBuilder path evaluates routing, path sanitization, forwardAuth, encodedCharacters, and access logging against a path normalized to / but forwards URL.Opaque verbatim to the backend, allowing cross-vhost routing bypass, path-scoped authorization bypass, and access-log evasion when the backend interprets the opaque target as a path. This issue is fixed in 2.11.57 and 3.7.13.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-1286",
"CWE-444"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/88xxx/CVE-2026-88009.json"
}{
"extracted_events": [
{
"cpe": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "0"
},
{
"fixed": "2.11.57"
}
],
"source": "CPE_RANGE"
},
{
"cpe": "cpe:2.3:a:traefik:traefik:*:*:*:*:*:*:*:*",
"range": [
{
"introduced": "3.0.0"
},
{
"fixed": "3.7.13"
}
],
"source": "CPE_RANGE"
},
{
"range": [
{
"fixed": "58d1e9ca204526823211e30fd4634101c59d58e9"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v2.11.57",
"range": [
{
"fixed": "839eb7f48a16849f22762b7e3bdfc58253146cd7"
}
],
"source": "REFERENCES_TAG"
},
{
"original_tag": "v3.7.13",
"range": [
{
"fixed": "fc92cc118a0557a029c7019d5ee06665127b0f13"
}
],
"source": "REFERENCES_TAG"
}
]
}