CVE-2024-49769 Waitress has a denial of service leading to high CPU usage/resource exhaustion
A remote attacker can cause high CPU usage and resource exhaustion in Waitress by closing connections prematurely, leading to a busy-loop.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-49769?
CVE-2024-49769 is a high-severity denial of service vulnerability in Pylons waitress, published on 29 Oct 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Waitress is a Web Server Gateway Interface server for Python 2 and 3. 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. Waitress 3.0.1 contains fixes that remove the race condition.
Weakness: CWE-772
Which versions are affected by CVE-2024-49769?
3 open source packages ship an affected version, including waitress. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
waitress PyPI | All versions | 3.0.1 |
waitress PyPI | All versions | 3.0.1 |
waitress PyPI | All versions | 3.0.1 |
Linux distribution packages (20)
python-waitress SUSE:Enterprise Storage 7.1 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise High Performance Computing 15 SP2-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise High Performance Computing 15 SP3-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise High Performance Computing 15 SP4-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Module for Basesystem 15 SP5 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Module for Basesystem 15 SP6 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Module for Package Hub 15 SP5 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Module for Package Hub 15 SP6 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server 15 SP2-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server 15 SP3-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server 15 SP4-LTSS | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server for SAP Applications 15 SP2 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server for SAP Applications 15 SP3 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Linux Enterprise Server for SAP Applications 15 SP4 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Manager Proxy 4.3 | All versions | 1.4.3-150000.3.9.1 |
python-waitress SUSE:Manager Server 4.3 | All versions | 1.4.3-150000.3.9.1 |
python-waitress openSUSE:Leap 15.5 | All versions | 1.4.3-150000.3.9.1 |
python-waitress openSUSE:Tumbleweed | All versions | 3.0.1-1.1 |
python-waitress openSUSE:Tumbleweed | All versions | 3.0.2-1.7 |
Products include Agendaless Waitress.
How do I fix CVE-2024-49769?
Upgrade waitress to 3.0.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-49769 being exploited?
There is no known exploitation of CVE-2024-49769 in the wild and no public exploit code.
Other vulnerabilities in Pylons waitress
- CVE-2024-49768 Waitress has request processing race condition in HTTP pipelining with invalid first request
- CVE-2022-24761 HTTP Request Smuggling in waitress
- CVE-2019-16792 HTTP Request Smuggling: Content-Length Sent Twice in Waitress
- CVE-2019-16789 HTTP Request Smuggling in Waitress: Invalid whitespace characters in headers
- CVE-2019-16785 HTTP Request Smuggling: LF vs CRLF handling in Waitress
Sources
Also known as AZL-51822, AZL-51831, CLSA-2025-1750810248, DEBIAN-CVE-2024-49769, DLA-3955-1, ECHO-283f-0619-628b and 11 more.