{"id":"CVE-2026-63405","sourceIdentifier":"security-advisories@github.com","published":"2026-09-18T17:16:59.463","lastModified":"2026-09-24T21:25:27.050","vulnStatus":"Deferred","cveTags":[],"descriptions":[{"lang":"en","value":"AnyCable is a realtime server for reliable two-way communication that supports any backend. Prior to 1.6.15, the Pusher-compatible REST API in pusher/http.go includes the caller-supplied body_md5 value in the HMAC input but does not calculate the digest of the received request body or compare it with the signed value. An attacker who obtains a legitimate signed POST request can retain its query parameters and auth_signature while replacing the body, causing Handler and handleEvents to accept and broadcast attacker-selected event content. The absence of an auth_timestamp freshness check also allows the captured signature to be replayed indefinitely. This can forge server-side events, modify application state, or deliver attacker-controlled messages to WebSocket clients within the signed request's application context. This issue is fixed in version 1.6.15."}],"affected":[{"source":"security-advisories@github.com","affectedData":[{"vendor":"anycable","product":"anycable","versions":[{"version":"< 1.6.15","status":"affected"}]}]}],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N","baseScore":5.9,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"HIGH","availabilityImpact":"NONE"},"exploitabilityScore":2.2,"impactScore":3.6}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-09-18T17:07:09.768503Z","id":"CVE-2026-63405","options":[{"exploitation":"poc"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"security-advisories@github.com","type":"Secondary","description":[{"lang":"en","value":"CWE-345"}]}],"references":[{"url":"https://github.com/anycable/anycable/commit/d2cbadec792f038f4695c84a65c0d957b0fde72c","source":"security-advisories@github.com"},{"url":"https://github.com/anycable/anycable/releases/tag/v1.6.15","source":"security-advisories@github.com"},{"url":"https://github.com/anycable/anycable/security/advisories/GHSA-5p54-whvp-x327","source":"security-advisories@github.com"},{"url":"https://github.com/anycable/anycable/security/advisories/GHSA-5p54-whvp-x327","source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}