Quick answers
- Is CVE-2024-39691 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2024-39691 being exploited in the wild.
- How severe is CVE-2024-39691?
- Low severity, with a CVSS score of 3.1, published 5 July 2024.
- Which products and versions are affected?
- Matrix.org Appservice IRC <= 2.0.0; matrix-appservice-irc (npm) SEMVER:introduced=0,fixed=2.0.1.
- Is there a fix for CVE-2024-39691?
- Yes. matrix-appservice-irc (npm): upgrade to 2.0.1 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2024-39691 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2024-39691?
- Check whether you run Matrix.org Appservice IRC or matrix-appservice-irc (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- matrix-appservice-irc (npm): upgrade to 2.0.1 or later
npm install matrix-appservice-irc@2.0.1
Technical details
The vulnerability is an insecure data validation issue (CWE-280, CWE-755) in the matrix-appservice-irc bridge. The bridge uses a homeserver-provided timestamp (origin_server_ts) to determine if a user has access to an event before including truncated message content in IRC replies. Since an external Matrix homeserver controls this timestamp, a malicious homeserver can fabricate it to bypass access control checks and trick the bridge into leaking room messages it should not have visibility into. The attack requires the malicious homeserver to be joined to a room with the bridge. Fixed in version 2.0.1 by replacing timestamp-based validation with internally-tracked event timestamps.
Affected products
- Matrix.org AppService IRC <= 2.0.0
Identifiers
- CVE-2024-39691
- GHSA-w9mh-5x8j-9754
Timeline
- 2024-07-05: disclosed
- 2024-07-05: patched: Version 2.0.1 released