DoS Vulnerability in AIOHTTP Framework Affects Python Developers
CVE-2025-69227

6.6MEDIUM

Key Information:

Vendor

Aio-libs

Status
Aiohttp
Vendor
CVE Published:
5 January 2026

What is CVE-2025-69227?

The AIOHTTP framework, used for asynchronous HTTP client and server development in Python, has a vulnerability that allows attackers to exploit an infinite loop condition. This flaw occurs when assert statements within the code are bypassed, particularly impacting applications utilizing the Request.post() method when optimizations are enabled. When a specially crafted POST request is processed, it can lead to a Denial of Service, rendering the affected service unresponsive. Users are advised to upgrade to AIOHTTP version 3.13.3 or higher to mitigate this issue.

Affected Version(s)

aiohttp < 3.13.3

References

https://github.com/aio-libs/aiohttp/security/advisories/G...
x_refsource_CONFIRM
https://github.com/aio-libs/aiohttp/commit/bc1319ec3cbff9...
x_refsource_MISC

CVSS V4

Score:
6.6
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.