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.
CVSS Details
- CVSS 3.1 Base Score: 7.5
- CVSS 3.0 Vector: (CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | debian-upgrade-gunicorn | Dec 23, 2024 | Apr 16, 2024 | |
| Redhat_linux | — | no-fix-redhat-rpm-package | Jul 9, 2025 | Apr 16, 2024 |
| Suse | — | suse-upgrade-python-gunicorn-docsuse-upgrade-python3-gunicornsuse-upgrade-python311-gunicornsuse-upgrade-python313-gunicorn | Apr 29, 2024 | Apr 16, 2024 |
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