CVE-2022-24761: 
Python vulnerability analysis and mitigation

CVE-2022-24761 affects Waitress, a Web Server Gateway Interface server for Python 2 and 3, versions 2.1.0 and prior. The vulnerability was discovered and disclosed in March 2022, involving HTTP request smuggling when Waitress is deployed behind a proxy that does not properly validate incoming HTTP requests against RFC7230 standards (GitHub Advisory).

The vulnerability stems from two key issues: 1) The use of Python's int() function to parse strings into integers, which incorrectly interprets values like '+10' as '10' or '0x01' as '1', contrary to the RFC7230 standard that requires only digits or hex digits, and 2) Waitress's improper handling of chunk extensions, where it discards them without validating for illegal characters. This can lead to inconsistent request interpretation between Waitress and the frontend proxy (GitHub Advisory, NVD).

When exploited, this vulnerability allows attackers to perform HTTP request smuggling attacks, where Waitress and the frontend proxy disagree on request boundaries. This discrepancy can lead to request smuggling via the front-end proxy to Waitress, potentially resulting in cache poisoning or unexpected information disclosure (GitHub Advisory, Debian Advisory).

The vulnerability has been patched in Waitress version 2.1.1. For users unable to upgrade immediately, a workaround is available by configuring the front-end proxy to strictly validate requests against the RFC7230 standard. However, since some proxy servers may lack this functionality, upgrading to the latest version of Waitress is strongly recommended (GitHub Advisory).