On a brpc::Server that sets both ServerOptions.auth and ServerOptions.internal_port, the HTTP built-in service exemption on internal_port can be abused to bypass authentication entirely. VerifyHttpRequest() returns true without checking any credential when a built-in service is requested on internal_port, and this verdict is not per - request: verification runs only for the first message of a connection and the result latches the connection. Sending a request such as GET /status to internal_port first authenticates the whole connection, after which every subsequent request dispatched on the same connection is handled without ever calling VerifyHttpRequest(). This lets a remote attacker reach ordinary (non-built-in, non-tabbed) authenticated services without supplying valid credentials whenever the server uses ServerOptions.internal_port together with an Authenticator. The fix restricts internal_port so that it carries only built-in and Tabbed services; requests for ordinary services sent to internal_port are rejected with EPREM / HTTP 403.
Mitigation / Fix: upgrade to 1.18.0 or apply PR https://github.com/apache/brpc/pull/3525 .
Users who rely on serving normal services on internal_port must move those requests to the port passed to Server::Start().
"}],"value":"On a brpc::Server that sets both ServerOptions.auth and ServerOptions.internal_port, the HTTP built-in service exemption on internal_port can be abused to bypass authentication entirely. VerifyHttpRequest() returns true without checking any credential when a built-in service is requested on internal_port, and this verdict is not per - request: verification runs only for the first message of a connection and the result latches the connection. Sending a request such as GET /status to internal_port first authenticates the whole connection, after which every subsequent request dispatched on the same connection is handled without ever calling VerifyHttpRequest(). This lets a remote attacker reach ordinary (non-built-in, non-tabbed) authenticated services without supplying valid credentials whenever the server uses ServerOptions.internal_port together with an Authenticator. The fix restricts internal_port so that it carries only built-in and Tabbed services; requests for ordinary services sent to internal_port are rejected with EPREM / HTTP 403. \n\n\n\nMitigation / Fix: upgrade to 1.18.0 or apply PR https://github.com/apache/brpc/pull/3525 . \n\n\n\nUsers who rely on serving normal services on internal_port must move those requests to the port passed to Server::Start()."}],"metrics":[{"other":{"content":{"text":"moderate"},"type":"Textual description of severity"},"scenarios":[{"lang":"en","value":"GENERAL"}]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-287","description":"CWE-287 Improper Authentication","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-10-21T12:17:42.903Z","orgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","shortName":"apache"},"references":[{"name":"PR-3525","url":"https://github.com/apache/brpc/pulls/3525"},{"tags":["vendor-advisory"],"url":"https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb"}],"source":{"discovery":"INTERNAL"},"title":"Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth","x_generator":{"engine":"Vulnogram 0.2.0"}}},"cveMetadata":{"assignerOrgId":"f0158376-9dc2-43b6-827c-5f631a4d8d09","assignerShortName":"apache","cveId":"CVE-2026-86249","datePublished":"2026-10-21T12:17:42.903Z","dateReserved":"2026-09-06T11:17:57.587Z","dateUpdated":"2026-10-21T12:17:42.903Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-10-21 13:20:04","lastModifiedDate":"2026-10-21 13:20:04","problem_types":["CWE-287","CWE-287 CWE-287 Improper Authentication"],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"86249","Ordinal":"1","Title":"Apache bRPC: Authentication bypass when a server sets ServerOpti","CVE":"CVE-2026-86249","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"86249","Ordinal":"1","NoteData":"On a brpc::Server that sets both ServerOptions.auth and ServerOptions.internal_port, the HTTP built-in service exemption on internal_port can be abused to bypass authentication entirely. VerifyHttpRequest() returns true without checking any credential when a built-in service is requested on internal_port, and this verdict is not per - request: verification runs only for the first message of a connection and the result latches the connection. Sending a request such as GET /status to internal_port first authenticates the whole connection, after which every subsequent request dispatched on the same connection is handled without ever calling VerifyHttpRequest(). This lets a remote attacker reach ordinary (non-built-in, non-tabbed) authenticated services without supplying valid credentials whenever the server uses ServerOptions.internal_port together with an Authenticator. The fix restricts internal_port so that it carries only built-in and Tabbed services; requests for ordinary services sent to internal_port are rejected with EPREM / HTTP 403. \n\n\n\nMitigation / Fix: upgrade to 1.18.0 or apply PR https://github.com/apache/brpc/pull/3525 . \n\n\n\nUsers who rely on serving normal services on internal_port must move those requests to the port passed to Server::Start().","Type":"Description","Title":"Apache bRPC: Authentication bypass when a server sets ServerOpti"}]}}}