Vulnerability · Published Sep 12, 2022 · Assigned by GitHub_M
CVE-2022-39200Signature checks not applied to some retrieved missing events
High 7.3
In plain English
A high-severity security flaw in dendrite from matrix-org. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 31% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/matrix-org/dendrite | 0.9.8 | GO-2022-0989 |
| Go | github.com/matrix-org/dendrite | 0.9.8 | GHSA-pfw4-xjgm-267c |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| matrix-org | dendrite | < 0.9.8 |
Weakness: CWE-347 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L