# GHSA-32gv-6cf3-wcmq: HTTP/2 DoS Attacks: Ping, Reset, and Settings Floods

> Remote attackers can cause denial of service in Twisted web servers with optional HTTP/2 support via ping, reset, or settings floods.

- **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:** 14 Mar 2022

## What is GHSA-32gv-6cf3-wcmq?

GHSA-32gv-6cf3-wcmq is a denial of service vulnerability in twisted, published on 14 Mar 2022. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

### Impact
Twisted web servers that utilize the optional HTTP/2 support suffer from the following flow-control related vulnerabilities:

Ping flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9512
Reset flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9514
Settings flood: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-9515

A Twisted web server supports HTTP/2 requests if you've installed the [`http2` optional dependency set](https://twistedmatrix.com/documents/19.2.0/installation/howto/optional.html).

### Workarounds
There are no workarounds.

### References
https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md

### For more information
If you have any questions or comments about this advisory:
* Open an issue in [Twisted's Trac](https://twistedmatrix.com/trac/)

## Which versions are affected by GHSA-32gv-6cf3-wcmq?

2 open source packages ship an affected version, including twisted.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `twisted` | PyPI | All versions | 19.10.0 |
| `twisted` | PyPI | All versions | 19.10.0 |

## How do I fix GHSA-32gv-6cf3-wcmq?

Upgrade twisted to 19.10.0 or later.

## Is GHSA-32gv-6cf3-wcmq being exploited?

There is no known exploitation of GHSA-32gv-6cf3-wcmq in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for GHSA-32gv-6cf3-wcmq and fix it if it is affected.

What it is: GHSA-32gv-6cf3-wcmq is a denial of service vulnerability in twisted, published on 14 Mar 2022. 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-32gv-6cf3-wcmq in the wild and no public exploit code.

Affected packages and fixed versions:
- twisted (PyPI): affected all versions; fixed in 19.10.0
- twisted (PyPI): affected all versions; fixed in 19.10.0

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-32gv-6cf3-wcmq/ (Markdown: https://insights.sbomify.com/GHSA-32gv-6cf3-wcmq/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/GHSA-32gv-6cf3-wcmq

---
From sbomify Insights: https://insights.sbomify.com/GHSA-32gv-6cf3-wcmq/
Summaries are generated and may contain mistakes; the official description above is the record.