CVE-2026-74758 Apache bRPC: Heap Use-After-Free in RTMP Abort Message Handling
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-74758?
CVE-2026-74758 is a vulnerability in Apache bRPC, published on 21 Oct 2026.
Official description
A heap use-after-free in the RTMP protocol component of Apache bRPC (versions < 1.18.0) allows a remote attacker to crash a bRPC RTMP server by sending a crafted Abort control message. No authentication or application-level request is required.
Root Cause: When an RTMP Abort control message names the chunk stream that is currently being parsed (the chunk stream carrying the message itself), RtmpChunkStream::OnAbortMessage calls RtmpContext::ClearChunkStream, which deletes the RtmpChunkStream while its Feed() is still running. After the message handler returns, Feed() continues to access members of the deleted object, resulting in a heap-use-after-free.
Affected Scenarios: bRPC servers that enable RTMP support (ServerOptions.rtmp_service set) and accept connections from untrusted networks.
How to Fix: 1. Upgrade bRPC to version 1.18.0, which fixes this issue. 2. Apply this patch: https://github.com/apache/brpc/pull/3452
The fix skips clearing the chunk stream when the Abort message targets the chunk stream that is currently being parsed.
Weakness: CWE-416
Which versions are affected by CVE-2026-74758?
How do I fix CVE-2026-74758?
No fix has been published for CVE-2026-74758 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-74758 being exploited?
There is no known exploitation of CVE-2026-74758 in the wild and no public exploit code.
Sources
Also known as GHSA-jhf7-xcw3-gmv5.