Vulnerability · Published Jan 5, 2026 · Assigned by GitHub_M
CVE-2025-69227AIOHTTP vulnerable to DoS when bypassing asserts
Medium 6.6
In plain English
A medium-severity infinite loop in aiohttp from aio-libs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 34% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
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 packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | py3-aiohttp | 3.13.3-r0 | ALPINE-CVE-2025-69227 |
| Alpine:v3.24 | py3-aiohttp | 3.13.3-r0 | ALPINE-CVE-2025-69227 |
| Debian:12 | python-aiohttp | 3.8.4-1+deb12u2 | DEBIAN-CVE-2025-69227 |
| Debian:13 | python-aiohttp | 3.11.16-1+deb13u1 | DEBIAN-CVE-2025-69227 |
| Debian:14 | python-aiohttp | 3.13.3-1 | DEBIAN-CVE-2025-69227 |
| PyPI | aiohttp | 3.13.3 | PYSEC-2026-1107 |
| PyPI | aiohttp | 3.13.3 | GHSA-jj3x-wxrx-4x23 |
| Ubuntu:25.10 | python-aiohttp | 3.11.16-1ubuntu0.1 | UBUNTU-CVE-2025-69227 |
Affected products (as reported)
Weakness: CWE-835 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U