CVE-2026-86249

What it is

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().

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering.

Exploit odds

0.6% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-10-21 13:20 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-30 17:17 UTC Last updatedMost recent change to the record

Details

Published

2026-10-21 13:20 UTC

Last modified

2026-10-30 17:17 UTC

Exploit probability

0.6% · EPSS, next 30 days

Weakness

CWE-287 · Improper authentication

Record status

Deferred

Attack profile CVSS 3.1 · 9.1

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

None