CVE-2024-52815High▾ TwilightSynapse allows a a malformed invite to break the invitee's `/sync`
▾ Twilight zone — High severity, or a signal on a lesser flaw
impact 41.3 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
Last analysed / modified upstream
0.5%
0.5% → 0.6%
Synapse versions before 1.120.1 fail to properly validate invites received over federation. This vulnerability allows a malicious server to send a specially crafted invite that disrupts the invited user's /sync functionality.
Synapse 1.120.1 rejects such invalid invites received over federation and restores the ability to sync for affected users.
Server administrators can disable federation from untrusted servers.
If you have any questions or comments about this advisory, please email us at security at element.io.
matrix-synapse < 1.120.1Upgrade to a patched release:
matrix-synapse 1.120.1Connected by shared product, vendor, weakness, or advisory.
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