CVE-2021-40824

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Summary

CVECVE-2021-40824
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-09-13 19:15:00 UTC
Updated2023-08-08 14:22:00 UTC
DescriptionA logic error in the room key sharing functionality of Element Android before 1.2.2 and matrix-android-sdk2 (aka Matrix SDK for Android) before 1.2.2 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 attacker to decrypt end-to-end encrypted messages sent by affected clients.

Risk And Classification

Problem Types: CWE-290

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Matrix Element All All All All
Application Matrix Matrix-android-sdk2 All All All All

References

ReferenceSourceLinkTags
Disclosing CVE-2021-40823 and CVE-2021-40824: E2EE vulnerability in multiple Matrix clients | Matrix.org MISC matrix.org
Release v1.2.2 · matrix-org/matrix-android-sdk2 · GitHub MISC github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 501918 Alpine Linux Security Update for riot-web
  • 503178 Alpine Linux Security Update for element-web
  • 506038 Alpine Linux Security Update for element-web
  • 630727 For Android Vulnerability CVE-2021-40824
  • 690038 Free Berkeley Software Distribution (FreeBSD) Security Update for matrix clients (93eb0e48-14ba-11ec-875e-901b0e9408dc)
  • 994936 Java (Maven) Security Update for org.matrix.android:matrix-android-sdk2 (GHSA-jjmc-4p83-pp26)
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