Waitress vulnerable to DoS leading to high CPU usage/resource exhaustion
Impact
When a remote client closes the connection before waitress has had the opportunity to call getpeername() waitress won't correctly clean up the connection leading to the main thread attempting to write to a socket that no longer exists, but not removing it from the list of sockets to attempt to process. This leads to a busy-loop calling the write function.
A remote attacker could run waitress out of available sockets with very little resources required.
Patches
Waitress 3.0.1 contains fixes that remove the race condition.
Workarounds
No work-around.
References
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | waitress | < 3.0.1 | 3.0.1 |
References
- https://github.com/Pylons/waitress/security/advisories/GHSA-3f84-rpwh-47g6
- https://github.com/Pylons/waitress/commit/1ae4e894c9f76543bee06584001583fc6fa8c95c
- https://github.com/Pylons/waitress/pull/435
- https://github.com/Pylons/waitress/issues/418
- https://lists.debian.org/debian-lts-announce/2024/11/msg00012.html
- https://nvd.nist.gov/vuln/detail/CVE-2024-49769
- https://github.com/Pylons/waitress
- https://github.com/pypa/advisory-database/tree/main/vulns/waitress/PYSEC-2024-211.yaml
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-772- Platform
- Python (PyPI)
- Package
waitress- Disclosed
- 29.10.2024
- Updated
- 11.10.2026 12:19
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2024-211 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-3f84-rpwh-47g6 - CC BY 4.0
Vulnerability history: waitress
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
- 10
- First → latest
- 12.2019 10.2024
- Without a fix
- 0
- Exploited in attacks
- 0
Severity breakdown
- Critical 2
- High 4
- Medium 4
Disclosures per year
- 2019: 5
- 2020: 1
- 2021: 0
- 2022: 2
- 2023: 0
- 2024: 2
- 2025: 0
- 2026: 0
-
Waitress vulnerable to DoS leading to high CPU usage/resource exhaustion this entry
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