matrix-appservice-irc events can be crafted to leak parts of targeted messages from other bridged rooms
Impact
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.
Patches
Please upgrade to 1.0.1.
Workarounds
You can set the matrixHandler.eventCacheSize config value to 0 to workaround this bug. However, this may impact performance.
Credits
Discovered and reported by Val Lorentz.
For more information
If you have any questions or comments about this advisory email us at security@matrix.org.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| npm package | matrix-appservice-irc | < 1.0.1 | 1.0.1 |
References
- https://github.com/matrix-org/matrix-appservice-irc/security/advisories/GHSA-c7hh-3v6c-fj4q
- https://nvd.nist.gov/vuln/detail/CVE-2023-38700
- https://github.com/matrix-org/matrix-appservice-irc/commit/8bbd2b69a16cbcbeffdd9b5c973fd89d61498d75
- https://github.com/matrix-org/matrix-appservice-irc
- https://github.com/matrix-org/matrix-appservice-irc/releases/tag/1.0.1
- CVSS vector
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N- Weakness (CWE)
CWE-200- Platform
- npm
- Package
matrix-appservice-irc- Disclosed
- 04.08.2023
- Updated
- 11.10.2026 10:22
Sources and licenses
OSV / GitHub Advisory Database - GHSA-c7hh-3v6c-fj4q - CC BY 4.0
Vulnerability history: matrix-appservice-irc
All published vulnerabilities of this package (npm package), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 9
- First → latest
- 05.2022 02.2025
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- High 2
- Medium 5
- Low 2
Disclosures per year
- 2022: 4
- 2023: 2
- 2024: 2
- 2025: 1
- 2026: 0
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matrix-appservice-irc events can be crafted to leak parts of targeted messages from other bridged rooms this entry
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