Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. In versions 3.13.2 and below, handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks. 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. This issue is fixed in version 3.13.3.
Published: 2026-01-05
Score: 6.6 Medium
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

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Remediation

No vendor fix or workaround currently provided.

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Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-6141-1 python-aiohttp security update
Github GHSA Github GHSA GHSA-g84x-mcqj-x9qq AIOHTTP vulnerable to DoS through chunked messages
History

Fri, 13 Feb 2026 19:00:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

 cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'}

Wed, 14 Jan 2026 19:30:00 +0000

Type Values Removed Values Added
CPEs cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*
Metrics cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N'}

 cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Tue, 06 Jan 2026 21:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Tue, 06 Jan 2026 14:30:00 +0000

Type Values Removed Values Added
First Time appeared Aio-libs
Aio-libs aiohttp Session
Aio-libs Project
Aio-libs Project aiohttp
Aiohttp
Aiohttp aio-libs
Aiohttp aiohttp
Vendors & Products Aio-libs
Aio-libs aiohttp Session
Aio-libs Project
Aio-libs Project aiohttp
Aiohttp
Aiohttp aio-libs
Aiohttp aiohttp

Tue, 06 Jan 2026 12:15:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.4, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N'}

threat_severity

Moderate

Mon, 05 Jan 2026 23:45:00 +0000

Type Values Removed Values Added
Description AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. In versions 3.13.2 and below, handling of chunked messages can result in excessive blocking CPU usage when receiving a large number of chunks. 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. This issue is fixed in version 3.13.3.
Title AIOHTTP vulnerable to DoS through chunked messages
Weaknesses CWE-770
References
Metrics cvssV4_0

{'score': 6.6, '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'}

Subscriptions

Aio-libs Aiohttp Session
Aio-libs Project Aiohttp
Aiohttp Aio-libs Aiohttp
cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-01-06T19:02:09.630Z

Reserved: 2025-12-29T20:53:34.537Z

Link: CVE-2025-69229

cve-icon Vulnrichment

Updated: 2026-01-06T14:24:48.256Z

cve-icon NVD

Status : Analyzed

Published: 2026-01-06T00:15:48.347

Modified: 2026-02-13T18:55:03.527

Link: CVE-2025-69229

cve-icon Redhat

Severity : Moderate

Publid Date: 2026-01-05T23:37:52Z

Links: CVE-2025-69229 - Bugzilla

cve-icon OpenCVE Enrichment

Updated: 2026-01-06T14:16:40Z

Weaknesses