CVE-2021-21333

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Summary

CVECVE-2021-21333
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-03-26 20:15:00 UTC
Updated2023-11-07 03:29:00 UTC
DescriptionSynapse is a Matrix reference homeserver written in python (pypi package matrix-synapse). Matrix is an ecosystem for open federated Instant Messaging and VoIP. In Synapse before version 1.27.0, the notification emails sent for notifications for missed messages or for an expiring account are subject to HTML injection. In the case of the notification for missed messages, this could allow an attacker to insert forged content into the email. The account expiry feature is not enabled by default and the HTML injection is not controllable by an attacker. This is fixed in version 1.27.0.

Risk And Classification

Problem Types: CWE-79

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Fedoraproject Fedora 34 All All All
Application Matrix Synapse All All All All

References

ReferenceSourceLinkTags
HTML injection in email and account expiry notifications · Advisory · matrix-org/synapse · GitHub CONFIRM github.com
Clean-up the template loading code by clokep · Pull Request #9200 · matrix-org/synapse · GitHub MISC github.com
Clean-up the template loading code. (#9200) · matrix-org/synapse@e54746b · GitHub MISC github.com
[SECURITY] Fedora 34 Update: matrix-synapse-1.38.1-1.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
[SECURITY] Fedora 34 Update: matrix-synapse-1.38.1-1.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
Release v1.27.0 · matrix-org/synapse · 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

  • 281765 Fedora Security Update for matrix (FEDORA-2021-a627cfd31e)
  • 981370 Python (pip) Security Update for matrix-synapse (GHSA-c5f8-35qr-q4fm)
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