CVE-2021-29433

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

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.

Categories

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.28%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: matrix-org sydent
Published at:
Updated at:

References

Link Tags
https://github.com/matrix-org/sydent/security/advisories/GHSA-pw4v-gr34-2553 third party advisory patch
https://github.com/matrix-org/sydent/commit/3175fd358ebc2c310eab7a3dbf296ce2bd54c1da third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-29433?
CVE-2021-29433 has been scored as a medium severity vulnerability.
How to fix CVE-2021-29433?
To fix CVE-2021-29433, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29433 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-29433 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29433?
CVE-2021-29433 affects matrix-org sydent.
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