CVE-2022-36009
Incorrect parsing of access level in gomatrixserverlib and dendrite
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
Description
gomatrixserverlib is a Go library for matrix protocol federation. Dendrite is a Matrix homeserver written in Go, an alternative to Synapse. The power level parsing within gomatrixserverlib was failing to parse the `"events_default"` key of the `m.room.power_levels` event, defaulting the event default power level to zero in all cases. Power levels are the matrix terminology for user access level. In rooms where the `"events_default"` power level had been changed, this could result in events either being incorrectly authorised or rejected by Dendrite servers. gomatrixserverlib contains a fix as of commit `723fd49` and Dendrite 0.9.3 has been updated accordingly. Matrix rooms where the `"events_default"` power level has not been changed from the default of zero are not vulnerable. Users are advised to upgrade. There are no known workarounds for this issue.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Medium5.0 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.86% · top 41% of all CVEs (6 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 5.0.
Weakness
Affected products
matrix-org · gomatrixserverlib
- affected < 0.9.3 for dendrite
- affected < 723fd49 for gomatrixserverlib
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- Gogithub.com/matrix-org/dendriteGHSA-grvv-h2f9-7v9c (opens in a new tab)
- Gogithub.com/matrix-org/gomatrixserverlibGHSA-grvv-h2f9-7v9c (opens in a new tab)
References (3)
- https://github.com/matrix-org/gomatrixserverlib/security/advisories/GHSA-grvv-h2f9-7v9c (opens in a new tab)x_refsource_CONFIRMx_transferred
- https://github.com/matrix-org/gomatrixserverlib/commit/723fd495dde835d078b9f2074b6b62c06dea4575 (opens in a new tab)x_refsource_MISCx_transferred
- https://matrix.org/docs/guides/moderation/#power-levels (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)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-grvv-h2f9-7v9c (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2022-36009)Record last updated .