CVE-2022-39203 — matrix-appservice-irc
HIGHCVE-2022-39203 is a high-severity (CVSS 8.8) Improper Privilege Management vulnerability in matrix-appservice-irc. A fix is available for matrix-appservice-irc — see the affected versions and patch details below.
Parsing issue in matrix-org/node-irc leading to room takeovers
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2022-39203.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
matrix-appservice-ircnpmDescription
Impact
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.
Patched
The vulnerability has been patched in matrix-appservice-irc 0.35.0.
Workarounds
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.
References
Credits
Discovered and reported by Val Lorentz.
For more information
If you have any questions or comments about this advisory email us at [email protected].
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | matrix-appservice-irc | all versions | 0.35.0npm install matrix-appservice-irc@0.35.0 |
Affected Products
matrix irc bridgematrixDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for matrix-appservice-irc, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update matrix-appservice-irc to 0.35.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2022-39203 is resolved across your whole dependency graph.
Workarounds
Close the privilege gap rather than the entry point: audit which accounts, roles and service identities can reach the affected operation, drop the component to the least privilege it actually needs, and review file and directory permissions created by earlier installs — a default left in place is what makes this reachable.
Frequently Asked Questions
Is CVE-2022-39203 in your dependencies?
Find it across npm, including transitive dependencies.