{"schema_version":"1.3.1","id":"GO-2026-6303","modified":"2026-08-28T14:47:45Z","published":"2026-08-28T14:47:45Z","aliases":["CVE-2026-56854"],"summary":"Source-address critical option not enforced for non-public-key auth callbacks in golang.org/x/crypto/ssh","details":"The source-address critical option in the Permissions returned by an authentication callback was only enforced for the PublicKeyCallback and VerifiedPublicKeyCallback paths, extending the fix for CVE-2026-46595. Permissions returned by the PasswordCallback, KeyboardInteractiveCallback, NoClientAuthCallback, and GSSAPIWithMICConfig.AllowLogin callbacks were not validated against the client's remote address, so a source-address restriction set by those callbacks was silently ignored. The check is now applied to the Permissions returned by any authentication callback.","affected":[{"package":{"name":"golang.org/x/crypto","ecosystem":"Go"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.55.0"}]}],"ecosystem_specific":{"imports":[{"path":"golang.org/x/crypto/ssh","symbols":["NewServerConn","connection.serverAuthenticate"]}]}}],"references":[{"type":"REPORT","url":"https://go.dev/issue/80213"},{"type":"FIX","url":"https://go.dev/cl/797040"}],"credits":[{"name":"Longwei Wang (@gn00295120)"}],"database_specific":{"url":"https://pkg.go.dev/vuln/GO-2026-6303","review_status":"REVIEWED"}}