CVE-2026-86249 Apache bRPC: Authentication bypass when a server sets ServerOptions.internal_port and ServerOptions.auth
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-86249?
CVE-2026-86249 is a vulnerability in Apache bRPC, published on 21 Oct 2026.
Official description
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().
Weakness: CWE-287
Which versions are affected by CVE-2026-86249?
How do I fix CVE-2026-86249?
No fix has been published for CVE-2026-86249 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-86249 being exploited?
There is no known exploitation of CVE-2026-86249 in the wild and no public exploit code.
Sources
Also known as GHSA-9hx3-v45m-g57x.