CVE-2025-69227: PYSEC-2026-1107 - AIOHTTP vulnerable to DoS when bypassing asserts

CVE-2025-69227 · Severity: high · CVSS 7.5 · Published 2026-01-06

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Versions 3.13.2 and below allow for an infinite loop to occur when assert statements are bypassed, resulting in a DoS attack when processing a POST body. If optimizations are enabled (-O or PYTHONOPTIMIZE=1), and the application includes a handler that uses the Request.post() method, then an attacker may be able to execute a DoS attack with a specially crafted message. This issue is fixed in version 3.13.3.

Technologies: Aiohttp, aiohttp (PyPI). Vendors: Aiohttp, PyPI.

Quick answers

Is CVE-2025-69227 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2025-69227 being exploited in the wild.
How severe is CVE-2025-69227?
High severity, with a CVSS score of 7.5, published 6 January 2026.
Which products and versions are affected?
aiohttp (PyPI) ECOSYSTEM:introduced=0,fixed=3.13.3.
Is there a fix for CVE-2025-69227?
Yes. aiohttp (PyPI): upgrade to 3.13.3 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
Am I affected by CVE-2025-69227?
Check whether you run Aiohttp or aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • aiohttp (PyPI): upgrade to 3.13.3 or later
    pip install "aiohttp>=3.13.3"

Affected products

  • Aiohttp
  • aiohttp (PyPI) ECOSYSTEM:introduced=0,fixed=3.13.3

Identifiers

  • CVE-2025-69227
  • GHSA-jj3x-wxrx-4x23
  • PYSEC-2026-1107

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