# CVE-2022-39203: Parsing issue in matrix-org/node-irc leading to room takeovers

> Attackers can exploit a parsing flaw in the Matrix IRC bridge to merge channels and grant themselves unauthorized permissions in existing rooms.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Sep 2022
- **Updated:** 23 Apr 2025
- **Also known as:** GHSA-xvqg-mv25-rwvw

## What is CVE-2022-39203?

CVE-2022-39203 is a high-severity vulnerability in matrix-org matrix-appservice-irc, published on 13 Sep 2022. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

matrix-appservice-irc is an open source Node.js IRC bridge for Matrix. Attackers can specify a specific string of characters, which would confuse the bridge into combining an attacker-owned channel and an existing channel, allowing them to grant themselves permissions in the channel. The vulnerability has been patched in matrix-appservice-irc 0.35.0. As a workaround operators may disable dynamic channel joining via `dynamicChannels.enabled` to prevent users from joining new channels, which prevents any new channels being bridged outside of what is already bridged, and what is specified in the config.

Weakness: CWE-269 (Improper Privilege Management)

## Which versions are affected by CVE-2022-39203?

2 open source packages ship an affected version, including matrix-appservice-irc. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `matrix-appservice-irc` | npm | All versions | 0.35.0 |
| `matrix-appservice-irc` | npm | All versions | 0.35.0 |

Products: Matrix Matrix Irc Bridge.

## How do I fix CVE-2022-39203?

Upgrade matrix-appservice-irc to 0.35.0 or later.

## Is CVE-2022-39203 being exploited?

There is no known exploitation of CVE-2022-39203 in the wild and no public exploit code.

## Other vulnerabilities in matrix-org matrix-appservice-irc

- [CVE-2022-29166](https://insights.sbomify.com/CVE-2022-29166/): Improper handling of multiline messages in matrix-appservice-irc (high 8.0)
- [CVE-2023-38690](https://insights.sbomify.com/CVE-2023-38690/): matrix-appservice-irc IRC command injection via admin commands containing newlines (medium 5.8)
- [CVE-2022-3971](https://insights.sbomify.com/CVE-2022-3971/): matrix-appservice-irc PgDataStore.ts sql injection (medium 4.6)
- [CVE-2022-39202](https://insights.sbomify.com/CVE-2022-39202/): IRC mode parameter confusion in matrix-appservice-irc (medium 4.3)
- [CVE-2023-38700](https://insights.sbomify.com/CVE-2023-38700/): matrix-appservice-irc events can be crafted to leak parts of targeted messages from other bridged rooms (low 3.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2022-39203 and fix it if it is affected.

What it is: CVE-2022-39203 is a high-severity vulnerability in matrix-org matrix-appservice-irc, published on 13 Sep 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2022-39203 in the wild and no public exploit code.

Affected packages and fixed versions:
- matrix-appservice-irc (npm): affected all versions; fixed in 0.35.0
- matrix-appservice-irc (npm): affected all versions; fixed in 0.35.0

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/CVE-2022-39203/ (Markdown: https://insights.sbomify.com/CVE-2022-39203/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-39203
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-39203
- OSV: https://osv.dev/vulnerability/CVE-2022-39203

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-39203/
Summaries are generated and may contain mistakes; the official description above is the record.