CVE-2021-29433

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

MEDIUM
4.3
CVSS Score
Published: April 15, 2021 at 05:55 PM UTC
Updated: June 17, 2026 at 03:47 AM UTC
2 products affected across 2 vendorsSydentSydent

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Severity
MEDIUM4.3
Exploit prediction
EPSS 0.9%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 2.3.0
Affected range stops below 2.3.0, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

4.3MEDIUMGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
LOW
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-20CWE-400

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