CVE-2026-34516: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.
AI Analysis
Technical Summary
The vulnerability CVE-2026-34516 in aiohttp, an asynchronous HTTP client/server framework for Python, arises from insufficient limits on resource allocation when handling responses containing many multipart headers. This flaw can cause excessive memory consumption, enabling a denial of service condition. The problem is fixed in version 3.13.4 of aiohttp.
Potential Impact
An attacker can cause aiohttp servers or clients running vulnerable versions to consume excessive memory by sending responses with a large number of multipart headers. This may lead to denial of service due to resource exhaustion. There are no indications of privilege escalation, code execution, or data disclosure associated with this vulnerability.
Mitigation Recommendations
Upgrade aiohttp to version 3.13.4 or later, where this vulnerability has been patched. No other mitigation steps are indicated or necessary.
CVE-2026-34516: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, a response with an excessive number of multipart headers may be allowed to use more memory than intended, potentially allowing a DoS vulnerability. This issue has been patched in version 3.13.4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-34516 in aiohttp, an asynchronous HTTP client/server framework for Python, arises from insufficient limits on resource allocation when handling responses containing many multipart headers. This flaw can cause excessive memory consumption, enabling a denial of service condition. The problem is fixed in version 3.13.4 of aiohttp.
Potential Impact
An attacker can cause aiohttp servers or clients running vulnerable versions to consume excessive memory by sending responses with a large number of multipart headers. This may lead to denial of service due to resource exhaustion. There are no indications of privilege escalation, code execution, or data disclosure associated with this vulnerability.
Mitigation Recommendations
Upgrade aiohttp to version 3.13.4 or later, where this vulnerability has been patched. No other mitigation steps are indicated or necessary.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-30T16:03:31.047Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 69cec35ce6bfc5ba1dfb4d65
Added to database: 4/2/2026, 7:28:28 PM
Last enriched: 4/9/2026, 10:39:29 PM
Last updated: 5/20/2026, 8:51:53 PM
Views: 65
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