Sydent DoS (via resource exhaustion) due to improper input validation
Impact
Missing 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.
Patches
Fixed by 3175fd3.
For more information
If you have any questions or comments about this advisory, email us at security@matrix.org.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | matrix-sydent | < 2.3.0 | 2.3.0 |
References
- https://github.com/matrix-org/sydent/security/advisories/GHSA-pw4v-gr34-2553
- https://pypi.org/project/matrix-sydent/
- https://nvd.nist.gov/vuln/detail/CVE-2021-29433
- https://github.com/matrix-org/sydent/commit/3175fd358ebc2c310eab7a3dbf296ce2bd54c1da
- https://github.com/matrix-org/sydent
- https://github.com/pypa/advisory-database/tree/main/vulns/matrix-sydent/PYSEC-2021-24.yaml
- https://pypi.org/project/matrix-sydent
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L- Weakness (CWE)
CWE-20, CWE-400- Platform
- Python (PyPI)
- Package
matrix-sydent- Disclosed
- 15.04.2021
- Updated
- 11.10.2026 15:17
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2021-24 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-pw4v-gr34-2553 - CC BY 4.0
Vulnerability history: matrix-sydent
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 7
- First → latest
- 05.2019 07.2023
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 1
- High 2
- Medium 4
Disclosures per year
- 2019: 1
- 2020: 0
- 2021: 4
- 2022: 1
- 2023: 1
- 2024: 0
- 2025: 0
- 2026: 0
-
Sydent DoS (via resource exhaustion) due to improper input validation this entry
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