CVE-2025-58068: 
Python vulnerability analysis and mitigation

Eventlet, a concurrent networking library for Python, was found to contain a vulnerability (CVE-2025-58068) in its WSGI parser prior to version 0.40.3. The vulnerability was discovered and disclosed on August 29, 2025, affecting all versions before 0.40.3. The issue stems from improper handling of HTTP trailer sections in the WSGI parser (GitHub Advisory).

The vulnerability is classified as an HTTP Request Smuggling issue (CWE-444) due to improper handling of HTTP trailer sections in the WSGI parser. The CVSS v4.0 base score is 6.3 (Medium), with the vector string CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N. The technical issue arose from the WSGI parser only reading one line after the final chunk, leaving trailers in the buffer, which could lead to request smuggling attacks (GitHub Commit).

The vulnerability could enable attackers to bypass front-end security controls, launch targeted attacks against active site users, and poison web caches. This poses a significant risk to systems using Eventlet's WSGI parser facing untrusted clients (GitHub Advisory).

The vulnerability has been patched in Eventlet version 0.40.3 by implementing logic to discard trailers. However, this is a breaking change if a backend behind eventlet.wsgi proxy requires trailers. As a workaround, users are advised not to use eventlet.wsgi facing untrusted clients if they cannot update to the patched version (GitHub Advisory).