How severe is CVE-2023-38690?

CVE-2023-38690 has a CVSS score of 5.8/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2023-38690?

CVE-2023-38690 affects the following packages: matrix-appservice-irc (npm). Ecosystems affected: npm.

How do I fix CVE-2023-38690?

Update matrix-appservice-irc to 1.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-38690 is resolved across your whole dependency graph.

How do I detect CVE-2023-38690 in my npm dependencies?

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.

How do I mitigate CVE-2023-38690 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is CVE-2023-38690 actively exploited in the wild?

No public exploit code has been indexed for CVE-2023-38690 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2023-38690?

CVE-2023-38690 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 59th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2023-38690?

CVE-2023-38690 is classified as Improper Input Validation (CWE-20), CWE-77 (CWE-77). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2023-38690 published, and has it been updated?

CVE-2023-38690 was published on August 4, 2023 and was last updated on October 28, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

CVE-2023-38690 — matrix-appservice-irc

MEDIUMFix: matrix-org/matrix-appservice-irc@0afb064

CVE-2023-38690 is a medium-severity (CVSS 5.8) Improper Input Validation vulnerability in matrix-appservice-irc. A fix is available for matrix-appservice-irc — see the affected versions and patch details below.

matrix-appservice-irc IRC command injection via admin commands containing newlines

Also known asGHSA-3pmj-jqqp-2mj3

Published

Aug 4, 2023

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
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-2023-38690.

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs59th percentile — riskier than 59% of all scored CVEsHighest risk

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

1 pkg affected

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.

0other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

matrix-appservice-ircnpm

407downloads / week

Description

Impact

It is possible to craft a command with newlines which would not be properly parsed. This would mean you could pass a string of commands as a channel name, which would then be run by the IRC bridge bot.

Patches

Versions 1.0.1 and above are patched.

Workarounds

There are no robust workarounds to the bug. You can disable dynamic channels in the config to disable the most common execution method but others may exist. It is highly recommended to upgrade the bridge.

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

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`matrix-appservice-irc`	all versions	1.0.1`npm install matrix-appservice-irc@1.0.1`

Affected Products

1 product · 1 configurations

Application

matrix irc bridgematrix

< 1.0.1

range

Detection & mitigation playbook

Open-source dependency

Detect
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 1.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-38690 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Frequently Asked Questions

### Impact It is possible to craft a command with newlines which would not be properly parsed. This would mean you could pass a string of commands as a channel name, which would then be run by the IRC bridge bot. ### Patches Versions 1.0.1 and above are patched. ### Workarounds There are no robust workarounds to the bug. You can disable dynamic channels in the config to disable the most common execution method but others may exist. It is highly recommended to upgrade the bridge. ### Credits Discovered and reported by [Val Lorentz](https://valentin-lorentz.fr/). ### For more informatio