GHSA-Q3QX-C6G2-7PW2
Vulnerability from github – Published: 2023-11-27 23:17 – Updated: 2025-11-03 22:32Summary
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.
Patch: https://github.com/aio-libs/aiohttp/pull/7835/files
{
"affected": [
{
"package": {
"ecosystem": "PyPI",
"name": "aiohttp"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "3.9.0"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2023-49081"
],
"database_specific": {
"cwe_ids": [
"CWE-20"
],
"github_reviewed": true,
"github_reviewed_at": "2023-11-27T23:17:42Z",
"nvd_published_at": "2023-11-30T07:15:08Z",
"severity": "MODERATE"
},
"details": "### Summary\nImproper 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.\n\n### Details\nThe vulnerability only occurs if the attacker can control the HTTP version of the request (including its type).\nFor 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.\nFurthermore, the vulnerability only occurs when the `Connection` header is passed to the `headers` parameter.\n\nAt 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.\n\n### PoC\nThe POC below shows an example of providing an unvalidated array as a version:\nhttps://gist.github.com/jnovikov/184afb593d9c2114d77f508e0ccd508e\n\n### Impact\nCRLF injection leading to Request Smuggling.\n\n### Workaround\nIf 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`.\n\nPatch: https://github.com/aio-libs/aiohttp/pull/7835/files",
"id": "GHSA-q3qx-c6g2-7pw2",
"modified": "2025-11-03T22:32:00Z",
"published": "2023-11-27T23:17:42Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/aio-libs/aiohttp/security/advisories/GHSA-q3qx-c6g2-7pw2"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2023-49081"
},
{
"type": "WEB",
"url": "https://github.com/aio-libs/aiohttp/pull/7835/files"
},
{
"type": "WEB",
"url": "https://github.com/aio-libs/aiohttp/commit/1e86b777e61cf4eefc7d92fa57fa19dcc676013b"
},
{
"type": "WEB",
"url": "https://gist.github.com/jnovikov/184afb593d9c2114d77f508e0ccd508e"
},
{
"type": "PACKAGE",
"url": "https://github.com/aio-libs/aiohttp"
},
{
"type": "WEB",
"url": "https://github.com/pypa/advisory-database/tree/main/vulns/aiohttp/PYSEC-2023-250.yaml"
},
{
"type": "WEB",
"url": "https://lists.debian.org/debian-lts-announce/2025/02/msg00002.html"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TY5SI6NK5243DEEDQUFKQKW5GQNKQUMA"
},
{
"type": "WEB",
"url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WSYWMP64ZFCTC3VO6RY6EC6VSSMV6I3A"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N",
"type": "CVSS_V3"
},
{
"score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N",
"type": "CVSS_V4"
}
],
"summary": "aiohttp\u0027s ClientSession is vulnerable to CRLF injection via version"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.