Echo is a Go web framework. Prior to 4.16.0 and 5.4.0, Echo's MethodOverride middleware accepts a safe HTTP method as the override target for a POST request. When MethodOverride is registered before CSRF in the post-routing middleware chain, route selection retains the original state-changing POST handler but the override changes the method before CSRF evaluates it, causing both token validation and Sec-Fetch-Site checks to be skipped. A cross-site exploit requires an authenticated victim and an override value that a browser-submitted request can control, such as the form getter used by the advisory reproducer; the default X-HTTP-Method-Override header getter is not settable by a cross-site form. This issue is fixed in 4.16.0 and 5.4.0.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-352"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/118xxx/CVE-2026-118266.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "4.16.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.4.0"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
},
{
"range": [
{
"fixed": "b838391e2eade87ae7e5a09d7bb5087bec271ec1"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "fc410094b2f3415cf2bf5204082137b205bfd5af"
}
],
"source": "REFERENCES_COMMIT"
},
{
"original_tag": "v4.16.0",
"range": [
{
"fixed": "e75c6c6d0c99602336fcf2c6bf6c8475ee160683"
}
],
"source": "REFERENCES_TAG"
},
{
"original_tag": "v5.4.0",
"range": [
{
"fixed": "fc410094b2f3415cf2bf5204082137b205bfd5af"
}
],
"source": "REFERENCES_TAG"
}
]
}