CVE-2026-34517: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
CVE-2026-34517 is a low-severity vulnerability in aiohttp versions prior to 3. 13. 4 where certain multipart form fields are fully read into memory before enforcing the client_max_size limit. This can lead to allocation of resources without proper limits or throttling. The issue has been addressed in aiohttp version 3. 13. 4.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-34517 affects aiohttp, an asynchronous HTTP client/server framework for Python. In versions before 3.13.4, aiohttp reads entire multipart form fields into memory before checking the configured client_max_size limit, potentially allowing excessive memory consumption. This behavior corresponds to CWE-770, which involves allocation of resources without limits or throttling. The vulnerability is rated with a CVSS 4.0 base score of 2.7 (low severity). The issue has been patched in version 3.13.4 of aiohttp.
Potential Impact
The impact of this vulnerability is limited to potential excessive memory usage when processing certain multipart form fields, which could degrade service performance or availability. There are no indications of remote code execution, privilege escalation, or data disclosure. No known exploits are reported in the wild.
Mitigation Recommendations
Upgrade aiohttp to version 3.13.4 or later, where this vulnerability has been fixed. Since this is a library used in applications, ensure that all deployments using aiohttp are updated accordingly. Patch status is confirmed by the vendor advisory indicating the fix in version 3.13.4.
CVE-2026-34517: CWE-770: Allocation of Resources Without Limits or Throttling in aio-libs aiohttp
Description
CVE-2026-34517 is a low-severity vulnerability in aiohttp versions prior to 3. 13. 4 where certain multipart form fields are fully read into memory before enforcing the client_max_size limit. This can lead to allocation of resources without proper limits or throttling. The issue has been addressed in aiohttp version 3. 13. 4.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-34517 affects aiohttp, an asynchronous HTTP client/server framework for Python. In versions before 3.13.4, aiohttp reads entire multipart form fields into memory before checking the configured client_max_size limit, potentially allowing excessive memory consumption. This behavior corresponds to CWE-770, which involves allocation of resources without limits or throttling. The vulnerability is rated with a CVSS 4.0 base score of 2.7 (low severity). The issue has been patched in version 3.13.4 of aiohttp.
Potential Impact
The impact of this vulnerability is limited to potential excessive memory usage when processing certain multipart form fields, which could degrade service performance or availability. There are no indications of remote code execution, privilege escalation, or data disclosure. No known exploits are reported in the wild.
Mitigation Recommendations
Upgrade aiohttp to version 3.13.4 or later, where this vulnerability has been fixed. Since this is a library used in applications, ensure that all deployments using aiohttp are updated accordingly. Patch status is confirmed by the vendor advisory indicating the fix in version 3.13.4.
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: 69cec35ae6bfc5ba1dfb4d05
Added to database: 4/2/2026, 7:28:26 PM
Last enriched: 4/10/2026, 12:02:06 AM
Last updated: 5/20/2026, 8:52:03 PM
Views: 74
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