# CVE-2026-82942: Apache bRPC: Race Condition on the Shared Socket Input Buffer in the RDMA Transport Causes Remote Denial of Service


- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 21 Oct 2026
- **Updated:** 21 Oct 2026
- **Also known as:** GHSA-54rx-jmrp-j5mw

## What is CVE-2026-82942?

CVE-2026-82942 is a vulnerability in Apache bRPC, published on 21 Oct 2026. 

### Official description

A data race in the RDMA transport of Apache bRPC (versions < 1.18.0) allows a remote client to crash the server process (denial of service) when RDMA is enabled at build time and runtime.

Root Cause:
When a bRPC server negotiates RDMA with a client, the handshake completes on the TCP fd, but the server kept parsing that fd afterwards as if it were still an RPC channel. The TCP-fd input stream and the RDMA QP input stream (driven by CQ events) shared the same Socket::_read_buf, preferred_index and parsing_context without synchronization. In addition, CQ event processing could start while the handshake parsing was still in progress, and the handshake ACK phase could consume bytes belonging to the next protocol. A remote, unauthenticated client that has completed the RDMA handshake can send data on the TCP fd at the same time RDMA messages are being processed, corrupting the shared input buffer and parser state and crashing the server process (CWE-362, availability impact).

Affected Scenarios:
Use a bRPC server with RDMA support enabled (built with BRPC_WITH_RDMA and serving rdma:// / SOCKET_MODE_RDMA sockets) and accept connections from untrusted clients. Deployments without RDMA are not affected.

How to Fix:
(Choose one of the following options)
1. Upgrade bRPC to version 1.18.0, which fixes this issue.
2. Apply this patch:  https://github.com/apache/brpc/pull/3505

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2026-82942?


## How do I fix CVE-2026-82942?

No fix has been published for CVE-2026-82942 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-82942 being exploited?

There is no known exploitation of CVE-2026-82942 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82942 and fix it if it is affected.

What it is: CVE-2026-82942 is a vulnerability in Apache bRPC, published on 21 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-82942 in the wild and no public exploit code.

Affected product: Apache bRPC. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-82942/ (Markdown: https://insights.sbomify.com/CVE-2026-82942/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82942
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82942
- OSV: https://osv.dev/vulnerability/CVE-2026-82942

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82942/
Summaries are generated and may contain mistakes; the official description above is the record.