CVE-2023-38700: 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 ...

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.

Metrics

CVSS 3.1

3.7/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS Probability

0.48%

38.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-200

Affected Software

Vendor	Product	Versions
Matrix	Matrix Irc Bridge	< 1.0.1

References

Timeline

Published: Aug 4, 2023
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2023-38700?

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.

How severe is CVE-2023-38700?

CVE-2023-38700 has a CVSS score of 3.7/10 (LOW severity). The EPSS model estimates a 0.48% probability of exploitation in the next 30 days.

How do I fix CVE-2023-38700?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.