CVE-2021-29433

Denial of service (via resource exhaustion) due to improper input validation

Published: Apr 15, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-20

4.3MEDIUM

Description

Sydent is a reference Matrix identity server. In Sydent versions 2.2.0 and prior, sissing 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. A patch for the vulnerability is in version 2.3.0. No workarounds are known to exist.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:LAvailability

Low

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Weaknesses

CWE-20 CWE-400

Affected Products

matrix

oss-project·GBaka synapse, matrix irc bridge, javascript sdk

sydentOn-prem

Communications / messaging-chat

matrix-org

oss-project·DEaka matrix appservice irc, synapse, matrix-js-sdk

sydent

Communications / messaging-chat

PyPI

package-ecosystem

matrix-sydent

OSS Libraries

Exploitability

Official Patch Available

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Impact

Initial Access

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References

https://github.com/matrix-org/sydent/commit/3175fd358ebc2c310eab7a3dbf296ce2bd54c1da

github.com

https://github.com/matrix-org/sydent/security/advisories/GHSA-pw4v-gr34-2553

github.com

https://nvd.nist.gov/vuln/detail/CVE-2021-29433

nvd.nist.gov

and 3 more references View all →

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