aiohttp's ClientSession is vulnerable to CRLF injection via version
Summary
Improper validation make it possible for an attacker to modify the HTTP request (e.g. to insert a new header) or even create a new HTTP request if the attacker controls the HTTP version.
Details
The vulnerability only occurs if the attacker can control the HTTP version of the request (including its type).
For example if an unvalidated JSON value is used as a version and the attacker is then able to pass an array as the version parameter.
Furthermore, the vulnerability only occurs when the Connection header is passed to the headers parameter.
At this point, the library will use the parsed value to create the request. If a list is passed, then it bypasses validation and it is possible to perform CRLF injection.
PoC
The POC below shows an example of providing an unvalidated array as a version: https://gist.github.com/jnovikov/184afb593d9c2114d77f508e0ccd508e
Impact
CRLF injection leading to Request Smuggling.
Workaround
If these specific conditions are met and you are unable to upgrade, then validate the user input to the version parameter to ensure it is a str.
Software afectado
Haz clic en una tecnología para ver todas sus vulnerabilidades.
| Plataforma | Paquete | Versiones vulnerables | Corregida en |
|---|---|---|---|
| Python (PyPI) | aiohttp | < 3.9.0 | 3.9.0 |
Referencias
- https://github.com/aio-libs/aiohttp/security/advisories/GHSA-q3qx-c6g2-7pw2
- https://gist.github.com/jnovikov/184afb593d9c2114d77f508e0ccd508e
- https://github.com/aio-libs/aiohttp/pull/7835/files
- https://github.com/aio-libs/aiohttp/commit/1e86b777e61cf4eefc7d92fa57fa19dcc676013b
- https://nvd.nist.gov/vuln/detail/CVE-2023-49081
- https://github.com/aio-libs/aiohttp
- https://github.com/pypa/advisory-database/tree/main/vulns/aiohttp/PYSEC-2023-250.yaml
- https://lists.debian.org/debian-lts-announce/2025/02/msg00002.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TY5SI6NK5243DEEDQUFKQKW5GQNKQUMA
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WSYWMP64ZFCTC3VO6RY6EC6VSSMV6I3A
- Vector CVSS
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N- Debilidad (CWE)
CWE-20- Plataforma
- Python (PyPI)
- Paquete
aiohttp- Publicada
- 27.11.2023
- Actualizado
- 11.10.2026 15:17
Fuentes y licencias
OSV / GitHub Advisory Database - PYSEC-2023-250 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-q3qx-c6g2-7pw2 - CC BY 4.0
Historial de vulnerabilidades: aiohttp
Todas las vulnerabilidades publicadas de este paquete (Python (PyPI)), de la más reciente a la más antigua. Muestra si es un fallo aislado o un paquete que hay que vigilar.
- Entradas en total
- 55
- Primera → última
- 02.2021 10.2026
- Sin corrección
- 0
- Explotada en ataques
- 0
Distribución por gravedad
- Alta 7
- Media 29
- Baja 19
Divulgaciones por año
- 2021: 1
- 2022: 0
- 2023: 6
- 2024: 7
- 2025: 1
- 2026: 40
-
aiohttp's ClientSession is vulnerable to CRLF injection via version esta entrada
Identifica las vulnerabilidades de tu aplicación
Con la integración de DockRay y el inventario de software activado, DockRay compara las versiones notificadas de los componentes con las vulnerabilidades conocidas y avisa de las coincidencias confirmadas. La cobertura depende de la tecnología compatible y de los avisos disponibles.