CVE-2021-29430

Summary

CVECVE-2021-29430
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-15 21:15:00 UTC
Updated2022-08-03 10:13:00 UTC
DescriptionSydent is a reference Matrix identity server. Sydent does not limit the size of requests it receives from HTTP clients. A malicious user could send an HTTP request with a very large body, leading to memory exhaustion and denial of service. Sydent also does not limit response size for requests it makes to remote Matrix homeservers. A malicious homeserver could return a very large response, again leading to memory exhaustion and denial of service. This affects any server which accepts registration requests from untrusted clients. This issue has been patched by releases 89071a1, 0523511, f56eee3. As a workaround request sizes can be limited in an HTTP reverse-proxy. There are no known workarounds for the problem with overlarge responses.

Risk And Classification

Problem Types: CWE-770

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Matrix Sydent All All All All

References

ReferenceSourceLinkTags
Release Sydent 2.3.0 (2021-04-15) · matrix-org/sydent · GitHub MISC github.com
matrix-sydent · PyPI MISC pypi.org
Add max size for other HTTP calls. · matrix-org/sydent@f56eee3 · GitHub MISC github.com
Limit the size of .well-known lookups. · matrix-org/sydent@0523511 · GitHub MISC github.com
Denial of service attack via disk space or memory exhaustion · Advisory · matrix-org/sydent · GitHub CONFIRM github.com
Limit maximum request size. · matrix-org/sydent@89071a1 · 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

  • 982748 Python (pip) Security Update for matrix-sydent (GHSA-wmg4-8cp2-hpg9)
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