CVE-2021-40823

CVSS V2 Medium 4.3 CVSS V3 Medium 5.9
Description
A logic error in the room key sharing functionality of matrix-js-sdk (aka Matrix Javascript SDK) before 12.4.1 allows a malicious Matrix homeserver present in an encrypted room to steal room encryption keys (via crafted Matrix protocol messages) that were originally sent by affected Matrix clients participating in that room. This allows the homeserver to decrypt end-to-end encrypted messages sent by affected clients.
Overview
  • CVE ID
  • CVE-2021-40823
  • Assigner
  • cve@mitre.org
  • Vulnerability Status
  • Analyzed
  • Published Version
  • 2021-09-13T19:15:19
  • Last Modified Date
  • 2021-09-24T17:27:00
Weakness Enumerations
CWE URL
CWE-327 http://cwe.mitre.org/data/definitions/327.html
CPE Configuration (Product)
CPE Vulnerable Operator Version Start Version End
cpe:2.3:a:matrix:javascript_sdk:*:*:*:*:*:*:*:* 1 OR 12.4.1
CVSS Version 2
  • Version
  • 2.0
  • Vector String
  • AV:N/AC:M/Au:N/C:P/I:N/A:N
  • Access Vector
  • NETWORK
  • Access Compatibility
  • MEDIUM
  • Authentication
  • NONE
  • Confidentiality Impact
  • PARTIAL
  • Integrity Impact
  • NONE
  • Availability Impact
  • NONE
  • Base Score
  • 4.3
  • Severity
  • MEDIUM
  • Exploitability Score
  • 8.6
  • Impact Score
  • 2.9
CVSS Version 3
  • Version
  • 3.1
  • Vector String
  • CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
  • Attack Vector
  • NETWORK
  • Attack Compatibility
  • HIGH
  • Privileges Required
  • NONE
  • User Interaction
  • NONE
  • Scope
  • UNCHANGED
  • Confidentiality Impact
  • HIGH
  • Availability Impact
  • NONE
  • Base Score
  • 5.9
  • Base Severity
  • MEDIUM
  • Exploitability Score
  • 2.2
  • Impact Score
  • 3.6
References
Reference URL Reference Tags
https://github.com/matrix-org/matrix-js-sdk/releases/tag/v12.4.1 Third Party Advisory
https://matrix.org/blog/2021/09/13/vulnerability-disclosure-key-sharing Vendor Advisory
Sources
Source Name Source URL
NIST https://nvd.nist.gov/vuln/detail/CVE-2021-40823
MITRE https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-40823
History
Created Old Value New Value Data Type Notes
2022-05-10 06:53:33 Added to TrackCVE
2022-12-05 10:27:20 2021-09-13T19:15Z 2021-09-13T19:15:19 CVE Published Date updated
2022-12-05 10:27:20 2021-09-24T17:27:00 CVE Modified Date updated
2022-12-05 10:27:20 Analyzed Vulnerability Status updated