CVE-2021-29431

Summary

CVECVE-2021-29431
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-04-15 21:15:00 UTC
Updated2021-04-22 15:27:00 UTC
DescriptionSydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration. This issue has been addressed in in 9e57334, 8936925, 3d531ed, 0f00412. A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.

Risk And Classification

Problem Types: CWE-20 | CWE-918

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Matrix Sydent All All All All

References

ReferenceSourceLinkTags
Add BlacklistingReactor · matrix-org/sydent@3d531ed · GitHub MISC github.com
Allow IPv6 literals as Matrix server names. · matrix-org/sydent@0f00412 · GitHub MISC github.com
Release Sydent 2.3.0 (2021-04-15) · matrix-org/sydent · GitHub MISC github.com
matrix-sydent · PyPI MISC pypi.org
Validate hostname in more places · matrix-org/sydent@8936925 · GitHub MISC github.com
Rework hostname validation to make port checking stricter. · matrix-org/sydent@9e57334 · GitHub MISC github.com
SSRF due to missing validation of hostnames · Advisory · matrix-org/sydent · GitHub CONFIRM github.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 982747 Python (pip) Security Update for matrix-sydent (GHSA-9jhm-8m8c-c3f4)
© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

CVE.report and Source URL Uptime Status status.cve.report