Vulnerability CVE-2021-29430


Published: 2021-04-15

Description:
Sydent 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.

Type:

CWE-20

(Improper Input Validation)

CVSS2 => (AV:N/AC:L/Au:N/C:N/I:N/A:P)

CVSS Base Score
Impact Subscore
Exploitability Subscore
5/10
2.9/10
10/10
Exploit range
Attack complexity
Authentication
Remote
Low
No required
Confidentiality impact
Integrity impact
Availability impact
None
None
Partial
Affected software
Matrix -> Sydent 

 References:
https://github.com/matrix-org/sydent/commit/0523511d2fb40f2738f8a8549868f44b96e5dab7
https://github.com/matrix-org/sydent/commit/89071a1a754c69a50deac89e6bb74002d4cda19d
https://github.com/matrix-org/sydent/commit/f56eee315b6c44fdd9f6aa785cc2ec744a594428
https://github.com/matrix-org/sydent/security/advisories/GHSA-wmg4-8cp2-hpg9
https://pypi.org/project/matrix-sydent/
https://github.com/matrix-org/sydent/releases/tag/v2.3.0

Copyright 2024, cxsecurity.com

 

Back to Top