How severe is GHSA-g84x-mcqj-x9qq?

No CVSS score has been assigned to GHSA-g84x-mcqj-x9qq yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by GHSA-g84x-mcqj-x9qq?

GHSA-g84x-mcqj-x9qq affects the following packages: aiohttp (PyPI). Ecosystems affected: PyPI.

How do I fix GHSA-g84x-mcqj-x9qq?

Update aiohttp to 3.13.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g84x-mcqj-x9qq is resolved across your whole dependency graph.

How do I detect GHSA-g84x-mcqj-x9qq in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-g84x-mcqj-x9qq if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is GHSA-g84x-mcqj-x9qq actively exploited in the wild?

No public exploit code has been indexed for GHSA-g84x-mcqj-x9qq yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-g84x-mcqj-x9qq?

GHSA-g84x-mcqj-x9qq has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 35th 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-g84x-mcqj-x9qq?

GHSA-g84x-mcqj-x9qq is classified as CWE-770 (CWE-770). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-g84x-mcqj-x9qq published, and has it been updated?

GHSA-g84x-mcqj-x9qq was published on January 5, 2026 and was last updated on September 10, 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

Not in CISA KEV

AIOHTTP vulnerable to DoS through chunked messagesGHSA-g84x-mcqj-x9qq

Fix: aio-libs/aiohttp@4ed97a4

GHSA-g84x-mcqj-x9qq is a CWE-770 vulnerability in aiohttp. A fix is available for aiohttp — see the affected versions and patch details below.

Also known asCVE-2025-69229PYSEC-2026-1106

Published

Jan 5, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 12, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-g84x-mcqj-x9qq.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs35th percentile — riskier than 35% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

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

Handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks.

Impact

If an application makes use of the request.read() method in an endpoint, it may be possible for an attacker to cause the server to spend a moderate amount of blocking CPU time (e.g. 1 second) while processing the request. This could potentially lead to DoS as the server would be unable to handle other requests during that time.

Patch: https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712 Patch: https://github.com/aio-libs/aiohttp/commit/4ed97a4e46eaf61bd0f05063245f613469700229

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`aiohttp`	all versions	3.13.3`pip install --upgrade 'aiohttp==3.13.3'`

Affected Products

1 product · 1 configurations

Application

aiohttpaiohttp

< 3.13.3

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for aiohttp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update aiohttp to 3.13.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-g84x-mcqj-x9qq is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

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.

Red HatModerate

This vulnerability is rated Moderate for Red Hat products. A flaw in the `aiohttp` library, used across various Red Hat offerings, allows an unauthenticated attacker to cause a Denial of Service. By sending a large number of chunks in an HTTP message, an attacker can trigger excessive CPU usage, rendering the affected…

Workaround published by Red Hat

No mitigation is currently available that meets Red Hat Product Security’s standards for usability, deployment, applicability, or stability.

Source: Red Hat security advisory for GHSA-g84x-mcqj-x9qq (CC BY 4.0)

Frequently Asked Questions

### Summary Handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks. ### Impact If an application makes use of the `request.read()` method in an endpoint, it may be possible for an attacker to cause the server to spend a moderate amount of blocking CPU time (e.g. 1 second) while processing the request. This could potentially lead to DoS as the server would be unable to handle other requests during that time. ----- Patch: https://github.com/aio-libs/aiohttp/commit/dc3170b56904bdf814228fae70a5501a42a6c712 Patch: https://github.com/aio-

O3 Security · Impact-Aware SCA

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