aiohttp is an asynchronous HTTP client/server framework that is used for building high-performance web applications using Python and asyncio. It simplifies the process of building web applications by handling complex tasks, such as handling connections, requests, and responses. However, a vulnerability has been discovered in aiohttp's Python parser that may allow attackers to execute request smuggling attacks under certain conditions. This vulnerability has been assigned the identifier CVE-2024-52304.
Vulnerability Details
Before version 3.10.11, aiohttp's Python parser incorrectly parsed newlines in chunk extensions. This issue may lead to request smuggling vulnerabilities if the pure Python version of aiohttp is installed (without the usual C extensions), or if the AIOHTTP_NO_EXTENSIONS environment variable is enabled. Request smuggling can enable an attacker to bypass security measures, such as firewalls or proxy protections, making affected systems more susceptible to unauthorized access.
The vulnerability has been fixed in aiohttp version 3.10.11. Users are strongly encouraged to update their installations to this version to mitigate the risk of exploitation.
Exploit Details
In vulnerable versions of aiohttp, an attacker can craft a specially formatted HTTP request with carefully placed newlines in chunk extensions. When this request is processed by aiohttp's Python parser, it may result in the splitting or combining of multiple requests, possibly leading to unauthorized access or bypassing security protections.
Here's an example of a malicious HTTP request that may be used to exploit this vulnerability
POST / HTTP/1.1
Host: example.com
Content-Type: text/plain
Transfer-Encoding: chunked
Content-Length: 5
3;foo=bar
baz
GET /secret HTTP/1.1
Host: example.com
Original References
1. Official aiohttp GitHub Repository: https://github.com/aio-libs/aiohttp
2. aiohttp 3.10.11 Release Notes: https://github.com/aio-libs/aiohttp/releases/tag/v3.10.11
3. CVE-2024-52304 Details: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2024-52304
Mitigation Steps
To remediate this vulnerability, users should update their aiohttp installations to version 3.10.11 or later. This can be done using the following command:
pip install --upgrade aiohttp==3.10.11
Additionally, it is recommended to avoid using the pure Python version of aiohttp or disabling C extensions if possible, as these configurations are more susceptible to this specific vulnerability.
Conclusion
CVE-2024-52304 is a request smuggling vulnerability in aiohttp's Python parser that can be exploited by attackers to bypass security protections or gain unauthorized access to an affected system. It is essential for developers and system administrators to update their aiohttp installations to version 3.10.11 or later to mitigate this risk. Regularly reviewing security advisories and applying patches in a timely manner is a crucial aspect of maintaining the security and reliability of web applications and services.
Timeline
Published on: 11/18/2024 21:15:06 UTC
Last modified on: 11/21/2024 14:15:17 UTC