CVE-2022-39335

Synapse does not apply enough checks to servers requesting auth events of events in a room

Published May 26, 2023 CVSS 3.1 · 5 Medium EPSS < 1% KEV · Not listed
Description
Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix Federation API allows remote homeservers to request the authorization events in a room. This is necessary so that a homeserver receiving some events can validate that those events are legitimate and permitted in their room. However, in versions of Synapse up to and including 1.68.0, a Synapse homeserver answering a query for authorization events does not sufficiently check that the requesting server should be able to access them. The issue was patched in Synapse 1.69.0. Homeserver administrators are advised to upgrade.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2023-0137 Synapse is an open-source Matrix homeserver written and maintained by the Matrix.org Foundation. The Matrix Federation API allows remote homeservers to request the authorization events in a room. This is necessary so that a homeserver receiving some events can validate that those events are legitimate and permitted in their room. However, in versions of Synapse up to and including 1.68.0, a Synapse homeserver answering a query for authorization events does not sufficiently check that the requesting server should be able to access them. The issue was patched in Synapse 1.69.0. Homeserver administrators are advised to upgrade.
Github GHSA Github GHSA GHSA-45cj-f97f-ggwv Synapse does not apply enough checks to servers requesting auth events of events in a room
Ubuntu USN Ubuntu USN USN-7444-1 Synapse vulnerabilities
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Feb 13, 2025, 4:32 PM
Reserved
Sep 2, 2022, 2:16 PM
Status
Modified
Published
May 26, 2023, 2:15 PM
Modified
Jun 17, 2026, 4:58 AM