CVE-2021-39163
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
02 Description
Adding a private/unlisted room to a community exposes room metadata in an unauthorised manner.
03 Exploitation and scoring
- Exploitation
- Not assessed. CISA has not published an exploitation assessment for this record, and it is not in the KEV catalog. That is an absence of assessment, not a finding of no risk.
- SSVC decision
- Not assessed by CISA
- EPSS probability
- 0.89% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 59.1% of scored records. A rank, not a probability.
- NVD base score
- 3.1 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
- NVD analysis status
- Modified. NVD last modified this record on 2026-06-17.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-08-31 16:00Z5 YR AGO
- Last updated
- 2024-08-04 01:58Z2 YR AGO
- Reserved
- 2021-08-16
- Assigning CNA
- GitHub_M
- Record state
- PUBLISHED
- Severity
- Low (CVSS 3.1)
- CNA CVSS vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
- Weaknesses
- Data version
- 5.1
- Document digest
- b2888ec68f8abbec9b6f4af815dcdb4d2cfda4d0cb3cb0a9be910d03bfb4572b
05 Affected products
06 References
- github.comhttps://github.com/matrix-org/synapse/security/advisories/GHSA-jj53-8fmw-f2w2
- github.comhttps://github.com/matrix-org/synapse/commit/cb35df940a
- github.comhttps://github.com/matrix-org/synapse/releases/tag/v1.41.1
- lists.fedoraproject.orgFEDORA-2021-2e8ed15b14https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/PXT7ID7DNBRN2TVTETU3SYQHJKEG6PXN/
- lists.fedoraproject.orgFEDORA-2021-f12fdca1bfhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/2VHDEPCZ22GJFMZCWA2XZAGPOEV72POF/
07 Fixed in
Arch Linux
- matrix-synapse Fixed in 1.41.1-1
Source: Arch Linux Security Tracker, the Arch Linux security team. Reformatted by exploit.cc.
Ubuntu Pro 18.04 LTS
- matrix-synapse No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 20.04 LTS
- matrix-synapse No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
Ubuntu Pro 22.04 LTS
- matrix-synapse No fix yet
Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.
A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.