CVE-2022-31152Synapse vulnerable to denial of service (DoS) due to incorrect application of event authorization rules
- 6.4MediumCVSS base score
- 1.2%Exploitation in 30 daysEPSS · top 31% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix specification specifies a list of [event authorization rules](https://spec.matrix.org/v1.2/rooms/v9/#authorization-rules) which must be checked when determining if an event should be accepted into a room. In versions of Synapse up to and including version 1.61.0, some of these rules are not correctly applied. An attacker could craft events which would be accepted by Synapse but not a spec-conformant server, potentially causing divergence in the room state between servers. Administrators of homeservers with federation enabled are advised to upgrade to version 1.62.0 or higher. Federation can be disabled by setting [`federation_domain_whitelist`](https://matrix-org.github.io/synapse/latest/usage/configuration/config_documentation.html#federation_domain_whitelist) to an empty list (`[]`) as a workaround.
Timeline
ID reserved
By GitHub_M
- 4 months later
· 4 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium6.4 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.2% · top 31% of all CVEs (12 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.4.
Affected products
- affected < 1.62.0
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- PyPImatrix-synapseGHSA-jhjh-776m-4765 (opens in a new tab)
References
References4
- https://github.com/matrix-org/synapse/security/advisories/GHSA-jhjh-776m-4765 (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/matrix-org/synapse/pull/13087 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/matrix-org/synapse/pull/13088 (opens in a new tab)x_refsource_MISCx_transferred
- https://github.com/matrix-org/synapse/releases/tag/v1.62.0 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2022-0154 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-jhjh-776m-4765 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2022-31152)Record last updated .