CVE-2024-53867: Synapse Matrix has a partial room state leak via Sliding Sync

4.3 CVSS

Description

Synapse is an open-source Matrix homeserver. The Sliding Sync feature on Synapse versions between 1.113.0rc1 and 1.120.0 can leak partial room state changes to users no longer in a room. Non-state events, like messages, are unaffected. This vulnerability is fixed in 1.120.1.

Classification

CVE ID: CVE-2024-53867

CVSS Base Severity: MEDIUM

CVSS Base Score: 4.3

Affected Products

Vendor: element-hq

Product: synapse

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 11.44% (scored less or equal to compared to others)

EPSS Date: 2025-02-03 (when was this score calculated)

References

https://github.com/element-hq/synapse/security/advisories/GHSA-56w4-5538-8v8h
https://github.com/matrix-org/matrix-spec-proposals/pull/4186

Timeline