CVE-2021-21393

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Summary

CVECVE-2021-21393
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-12 22:15:00 UTC
Updated2023-11-07 03:30:00 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 1.28.0 Synapse is missing input validation of some parameters on the endpoints used to confirm third-party identifiers could cause excessive use of disk space and memory leading to resource exhaustion. Note that the groups feature is not part of the Matrix specification and the chosen maximum lengths are arbitrary. Not all clients might abide by them. Refer to referenced GitHub security advisory for additional details including workarounds.

Risk And Classification

Problem Types: CWE-20

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
Type hints and validation improvements by clokep · Pull Request #9321 · matrix-org/synapse · GitHub MISC github.com
Denial of service (via resource exhaustion) due to improper input validation on groups/communities endpoints · Advisory · matrix-org/synapse · GitHub CONFIRM github.com
Add type hints to groups code by clokep · Pull Request #9393 · matrix-org/synapse · GitHub MISC github.com
[SECURITY] Fedora 34 Update: matrix-synapse-1.38.1-1.fc34 - package-announce - Fedora Mailing-Lists lists.fedoraproject.org
matrix-synapse · PyPI MISC pypi.org
[SECURITY] Fedora 34 Update: matrix-synapse-1.38.1-1.fc34 - package-announce - Fedora Mailing-Lists FEDORA lists.fedoraproject.org
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)
  • 981366 Python (pip) Security Update for matrix-synapse (GHSA-jrh7-mhhx-6h88)
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