---
id: CVE-2026-74758
title: 'Apache bRPC: Heap Use-After-Free in RTMP Abort Message Handling'
summary: >-
  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 re…
severity: none
cwe:
  - CWE-416
vendor: Apache Software Foundation
product: apache/brpc
affected:
  - apache/brpc < 1.18.0
published: '2026-10-21'
updated: '2026-10-21'
sourceUpdated: '2026-10-21T11:48:23.883Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-74758'
references:
  - url: 'https://lists.apache.org/thread/2pf15ojj0vr7rtx95677kgtl1mx3gdgb'
tags:
  - cve.org
ingestedAt: '2026-10-21T12:48:53.761Z'
---

## Overview

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.

## Affected

- `apache/brpc < 1.18.0`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.