How severe is GHSA-q3qx-c6g2-7pw2?

GHSA-q3qx-c6g2-7pw2 has a CVSS score of 7.2/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-q3qx-c6g2-7pw2?

GHSA-q3qx-c6g2-7pw2 affects the following packages: aiohttp (PyPI). Ecosystems affected: PyPI.

How do I fix GHSA-q3qx-c6g2-7pw2?

Update aiohttp to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q3qx-c6g2-7pw2 is resolved across your whole dependency graph.

How do I detect GHSA-q3qx-c6g2-7pw2 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-q3qx-c6g2-7pw2 if there is no patch (or I can't update yet)?

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 does O3 Security protect against GHSA-q3qx-c6g2-7pw2?

O3 pinpoints whether GHSA-q3qx-c6g2-7pw2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-q3qx-c6g2-7pw2 actively exploited in the wild?

Yes. There are 2 known exploit references for GHSA-q3qx-c6g2-7pw2, including 2 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for GHSA-q3qx-c6g2-7pw2?

GHSA-q3qx-c6g2-7pw2 has an EPSS (Exploit Prediction Scoring System) score of 0.9%, placing it in the 54th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-q3qx-c6g2-7pw2?

GHSA-q3qx-c6g2-7pw2 is classified as Improper Input Validation (CWE-20). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-q3qx-c6g2-7pw2 published, and has it been updated?

GHSA-q3qx-c6g2-7pw2 was published on November 27, 2023 and was last updated on February 4, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍 PyPI

GHSA-q3qx-c6g2-7pw2

HIGH

aiohttp's ClientSession is vulnerable to CRLF injection via version

Also known asCVE-2023-49081PYSEC-2023-250

Published

Nov 27, 2023

Updated

Feb 4, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

2 known

EPSS Exploitation Probability

via FIRST.org ↗

0.9%probability of exploitation in next 30 days

Lower Risk54th percentile+0.40%

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.

Blast Radius

1 pkg affected

🐍aiohttp

Real-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

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 Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`aiohttp`	all versions	3.9.0

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.

aiohttp is an asynchronous HTTP client/server framework for asyncio and …

github.comNVDDec 2023

aiohttp is an asynchronous HTTP client/server framework for asyncio and …

gist.github.comNVDDec 2023

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update aiohttp to 3.9.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-q3qx-c6g2-7pw2 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 pinpoints whether GHSA-q3qx-c6g2-7pw2 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-q3qx-c6g2-7pw2. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary 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 w

O3 Security · Impact-Aware SCA

Is GHSA-q3qx-c6g2-7pw2 in your dependencies?

O3 detects GHSA-q3qx-c6g2-7pw2 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works