# GHSA-xpw8-rcwv-8f8p: io.netty:netty-codec-http2 vulnerable to HTTP/2 Rapid Reset Attack

> Attackers can cause denial of service on HTTP/2 servers by sending frequent RST frames, requiring library upgrades to mitigate.

- **Severity:** Not scored
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 10 Oct 2023

## What is GHSA-xpw8-rcwv-8f8p?

GHSA-xpw8-rcwv-8f8p is a denial of service vulnerability in io.netty:netty-codec-http2, published on 10 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A client might overload the server by issue frequent RST frames. This can cause a massive amount of load on the remote system and so cause a DDOS attack. 

### Impact
This is a DDOS attack, any http2 server is affected and so you should update as soon as possible.

### Patches
This is patched in version 4.1.100.Final.

### Workarounds
A user can limit the amount of RST frames that are accepted per connection over a timeframe manually using either an own `Http2FrameListener` implementation or an `ChannelInboundHandler` implementation (depending which http2 API is used).

### References
- https://www.cve.org/CVERecord?id=CVE-2023-44487
- https://blog.cloudflare.com/technical-breakdown-http2-rapid-reset-ddos-attack/
- https://cloud.google.com/blog/products/identity-security/google-cloud-mitigated-largest-ddos-attack-peaking-above-398-million-rps/

## Which versions are affected by GHSA-xpw8-rcwv-8f8p?

2 open source packages ship an affected version, including io.netty:netty-codec-http2.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `io.netty:netty-codec-http2` | Maven | All versions | 4.1.100.Final |
| `io.netty:netty-codec-http2` | Maven | All versions | 4.1.100.Final |

## How do I fix GHSA-xpw8-rcwv-8f8p?

Upgrade io.netty:netty-codec-http2 to 4.1.100.Final or later.

## Is GHSA-xpw8-rcwv-8f8p being exploited?

There is no known exploitation of GHSA-xpw8-rcwv-8f8p in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-xpw8-rcwv-8f8p and fix it if it is affected.

What it is: GHSA-xpw8-rcwv-8f8p is a denial of service vulnerability in io.netty:netty-codec-http2, published on 10 Oct 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of GHSA-xpw8-rcwv-8f8p in the wild and no public exploit code.

Affected packages and fixed versions:
- io.netty:netty-codec-http2 (Maven): affected all versions; fixed in 4.1.100.Final
- io.netty:netty-codec-http2 (Maven): affected all versions; fixed in 4.1.100.Final

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/GHSA-xpw8-rcwv-8f8p/ (Markdown: https://insights.sbomify.com/GHSA-xpw8-rcwv-8f8p/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-xpw8-rcwv-8f8p

---
From sbomify Insights: https://insights.sbomify.com/GHSA-xpw8-rcwv-8f8p/
Summaries are generated and may contain mistakes; the official description above is the record.