# CVE-2026-82953: Apache bRPC: NULL Pointer Dereference in RTMP createStream Error Path Leading to Remote Denial of Service


- **Severity:** Medium 5.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Fix available:** No
- **Published:** 21 Oct 2026
- **Updated:** 26 Oct 2026
- **Also known as:** GHSA-389h-hr53-4f3g

## What is CVE-2026-82953?

CVE-2026-82953 is a medium-severity vulnerability in Apache bRPC, published on 21 Oct 2026. 

### Official description

NULL pointer dereference in the RTMP protocol implementation in Apache bRPC (version < 1.18.0) on all platforms allows remote attackers to crash the server (denial of service) via a crafted createStream command.

Root Cause:
When an RTMP service rejects a createStream request by returning a null stream from RtmpService::NewStream(), the server sends an error response to the client. If writing this rejection response fails (for example, because the client closes the connection immediately after sending the createStream command), the error-handling path in RtmpChunkStream::OnCreateStream() dereferences the null stream pointer to access stream->_onfail_id, causing the process to crash.

Affected Scenarios:
Run an Apache bRPC RTMP server whose RtmpService::NewStream() may return null (i.e., the service rejects createStream requests). A remote client that sends a createStream command and then closes the connection before the rejection response is written can crash the server.

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/3508

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2026-82953?


## How do I fix CVE-2026-82953?

No fix has been published for CVE-2026-82953 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-82953 being exploited?

There is no known exploitation of CVE-2026-82953 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-82953 and fix it if it is affected.

What it is: CVE-2026-82953 is a medium-severity vulnerability in Apache bRPC, published on 21 Oct 2026. 
Exploitation: There is no known exploitation of CVE-2026-82953 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-2026-82953/ (Markdown: https://insights.sbomify.com/CVE-2026-82953/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-82953
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-82953
- OSV: https://osv.dev/vulnerability/CVE-2026-82953

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-82953/
Summaries are generated and may contain mistakes; the official description above is the record.