Medium severity · published Apr 15, 2021
CVE-2021-29433
Denial of service (via resource exhaustion) due to improper input validation
4.3
CVSS
0.9%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 60% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
SY
sydent · matrix-org
<= 2.2.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-29433
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-29433
Patch
https://github.com/matrix-org/sydent/commit/3175fd358ebc2c310eab7a3dbf296ce2bd54c1da
Patch
https://github.com/matrix-org/sydent/security/advisories/GHSA-pw4v-gr34-2553
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