Vulnerability · Published Apr 16, 2024 · Assigned by @huntr_ai
CVE-2024-1135HTTP Request Smuggling in benoitc/gunicorn
High 7.5
In plain English
A high-severity security flaw in benoitc/gunicorn from benoitc. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 3.0% (higher than 87% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | gunicorn | 20.1.0-6+deb12u1 | DEBIAN-CVE-2024-1135 |
| Debian:13 | gunicorn | 22.0.0-1 | DEBIAN-CVE-2024-1135 |
| Debian:14 | gunicorn | 22.0.0-1 | DEBIAN-CVE-2024-1135 |
| PyPI | gunicorn | 22.0.0 | GHSA-w3h3-4rj7-4ph4 |
| PyPI | gunicorn | 22.0.0 | PYSEC-2026-1434 |
| Ubuntu:22.04:LTS | gunicorn | no fix listed | UBUNTU-CVE-2024-1135 |
| Ubuntu:24.04:LTS | gunicorn | no fix listed | UBUNTU-CVE-2024-1135 |
| Ubuntu:25.10 | gunicorn | no fix listed | UBUNTU-CVE-2024-1135 |
| Ubuntu:26.04:LTS | gunicorn | no fix listed | UBUNTU-CVE-2024-1135 |
| Ubuntu:26.10 | gunicorn | no fix listed | UBUNTU-CVE-2024-1135 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| benoitc | benoitc/gunicorn | unspecified – through latest |
Weakness: CWE-444 · Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N