Description
Gunicorn fails to properly validate Transfer-Encoding headers, leading to HTTP Request Smuggling (HRS) vulnerabilities. By crafting requests with conflicting Transfer-Encoding headers, attackers can bypass security restrictions and access restricted endpoints. This issue is due to Gunicorn's handling of Transfer-Encoding headers, where it incorrectly processes requests with multiple, conflicting Transfer-Encoding headers, treating them as chunked regardless of the final encoding specified. This vulnerability allows for a range of attacks including cache poisoning, session manipulation, and data exposure.
Scores
CVSS v3
7.5
EPSS
0.0004
EPSS Percentile
11.8%
Attack Vector
NETWORK
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
total
Details
CWE
CWE-444
Status
published
Products (2)
benoitc/benoitc/gunicorn
unspecified - latest
pypi/gunicorn
0 - 22.0.0PyPI
Published
Apr 16, 2024
Tracked Since
Feb 18, 2026