Description
Gunicorn version 21.2.0 does not properly validate the value of the 'Transfer-Encoding' header as specified in the RFC standards, which leads to the default fallback method of 'Content-Length,' making it vulnerable to TE.CL request smuggling. This vulnerability can lead to cache poisoning, data exposure, session manipulation, SSRF, XSS, DoS, data integrity compromise, security bypass, information leakage, and business logic abuse.
Scores
CVSS v3
7.5
EPSS
0.0005
EPSS Percentile
14.8%
Attack Vector
NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CISA SSVC
Vulnrichment
Exploitation
poc
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-444
Status
published
Products (2)
benoitc/benoitc/gunicorn
unspecified - latest
pypi/gunicorn
0 - 22.0.0PyPI
Published
Mar 20, 2025
Tracked Since
Feb 18, 2026