CVE-2023-37276 – aiohttp

Package

Manager: pip
Name: aiohttp
Vulnerable Version: >=0 <3.8.5

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

EPSS: 0.05775 pctl0.90127

Details

aiohttp.web.Application vulnerable to HTTP request smuggling via llhttp HTTP request parser ### Impact aiohttp v3.8.4 and earlier are [bundled with llhttp v6.0.6](https://github.com/aio-libs/aiohttp/blob/v3.8.4/.gitmodules) which is vulnerable to CVE-2023-30589. The vulnerable code is used by aiohttp for its HTTP request parser when available which is the default case when installing from a wheel. This vulnerability only affects users of aiohttp as an HTTP server (ie `aiohttp.Application`), you are not affected by this vulnerability if you are using aiohttp as an HTTP client library (ie `aiohttp.ClientSession`). ### Reproducer ```python from aiohttp import web async def example(request: web.Request): headers = dict(request.headers) body = await request.content.read() return web.Response(text=f"headers: {headers} body: {body}") app = web.Application() app.add_routes([web.post('/', example)]) web.run_app(app) ``` Sending a crafted HTTP request will cause the server to misinterpret one of the HTTP header values leading to HTTP request smuggling. ```console $ printf "POST / HTTP/1.1\r\nHost: localhost:8080\r\nX-Abc: \rxTransfer-Encoding: chunked\r\n\r\n1\r\nA\r\n0\r\n\r\n" \ | nc localhost 8080 Expected output: headers: {'Host': 'localhost:8080', 'X-Abc': '\rxTransfer-Encoding: chunked'} body: b'' Actual output (note that 'Transfer-Encoding: chunked' is an HTTP header now and body is treated differently) headers: {'Host': 'localhost:8080', 'X-Abc': '', 'Transfer-Encoding': 'chunked'} body: b'A' ``` ### Patches Upgrade to the latest version of aiohttp to resolve this vulnerability. It has been fixed in v3.8.5: [`pip install aiohttp >= 3.8.5`](https://pypi.org/project/aiohttp/3.8.5/) ### Workarounds If you aren't able to upgrade you can reinstall aiohttp using `AIOHTTP_NO_EXTENSIONS=1` as an environment variable to disable the llhttp HTTP request parser implementation. The pure Python implementation isn't vulnerable to request smuggling: ```console $ python -m pip uninstall --yes aiohttp $ AIOHTTP_NO_EXTENSIONS=1 python -m pip install --no-binary=aiohttp --no-cache aiohttp ``` ### References * https://nvd.nist.gov/vuln/detail/CVE-2023-30589 * https://hackerone.com/reports/2001873

Metadata

Created: 2023-07-20T14:52:00Z
Modified: 2024-09-03T21:33:36Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2023/07/GHSA-45c4-8wx5-qw6w/GHSA-45c4-8wx5-qw6w.json
CWE IDs: ["CWE-444"]
Alternative ID: GHSA-45c4-8wx5-qw6w
Finding: F110
Auto approve: 1