CVE-2022-39200 - CVE House
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Status published High CVE-2022-39200

Signature checks not applied to some retrieved missing events

Vulnerability Description

Dendrite is a Matrix homeserver written in Go. In affected versions events retrieved from a remote homeserver using the `/get_missing_events` path did not have their signatures verified correctly. This could potentially allow a remote homeserver to provide invalid/modified events to Dendrite via this endpoint. Note that this does not apply to events retrieved through other endpoints (e.g. `/event`, `/state`) as they have been correctly verified. Homeservers that have federation disabled are not vulnerable. The problem has been fixed in Dendrite 0.9.8. Users are advised to upgrade. There are no known workarounds for this issue.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

dendrite
Vulnerable Versions:
< 0.9.8

Timeline

Official Publish: September 12th, 2022
Last Modified: April 23rd, 2025
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Weaknesses (CWE)

CWE-347

MITRE ATT&CK TTPs

T1553 Subvert Trust Controls
Defense Evasion
T1190 Exploit Public-Facing Application
Initial Access
T1078 Valid Accounts
Persistence
T1550 Use Alternate Authentication Material
Defense Evasion
T1565 Data Manipulation
Impact