CVE-2023-38700

matrix-appservice-irc events can be crafted to leak parts of targeted messages from other bridged rooms

Description

matrix-appservice-irc is a Node.js IRC bridge for Matrix. Prior to version 1.0.1, it was possible to craft an event such that it would leak part of a targeted message event from another bridged room. This required knowing an event ID to target. Version 1.0.1n fixes this issue. As a workaround, set the `matrixHandler.eventCacheSize` config value to `0`. This workaround may impact performance.

Category

3.5
CVSS
Severity: Low
CVSS 3.1 •
EPSS 0.27%
Vendor Advisory github.com
Affected: matrix-org matrix-appservice-irc
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/matrix-appservice-irc/security/advisories/GHSA-c7hh-3v6c-fj4q vendor advisory
https://github.com/matrix-org/matrix-appservice-irc/commit/8bbd2b69a16cbcbeffdd9b5c973fd89d61498d75 patch
https://github.com/matrix-org/matrix-appservice-irc/releases/tag/1.0.1 release notes

Frequently Asked Questions

What is the severity of CVE-2023-38700?
CVE-2023-38700 has been scored as a low severity vulnerability.
How to fix CVE-2023-38700?
To fix CVE-2023-38700, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-38700 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-38700 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-38700?
CVE-2023-38700 affects matrix-org matrix-appservice-irc.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.