CVE-2024-53867

unknown

Published 2024-12-03 · Modified 2024-12-03

CVSS v3

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

CVSS v2

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VIR risk

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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.

Predictions

Exploit likelihood

30%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2024-53867

OS impact

OS	Version	Status	Fixed in
debian	forky	fixed	`1.121.0-1`
debian	sid	fixed	`1.121.0-1`

Package impact

Ecosystem	Package	Vulnerable	Fixed
PyPI	matrix-synapse	`>=1.113.0rc1,<1.120.1`	`1.120.1`

References

https://github.com/element-hq/synapse/security/advisories/GHSA-56w4-5538-8v8h
https://nvd.nist.gov/vuln/detail/CVE-2024-53867
https://github.com/matrix-org/matrix-spec-proposals/pull/4186
https://github.com/element-hq/synapse
https://security-tracker.debian.org/tracker/CVE-2024-53867

Verify integrity in audit chain (admin only). AS-IS.