CVE-2025-69227: Aiohttp

High severity, CVSS 7.5. EPSS: 0.4% chance of exploitation in the next 30 days.

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.

Affected products

• Aiohttp Aiohttp: before 3.13.3 (fixed in 3.13.3)

Published 2026-01-06. Last modified 2026-09-30.