CVE-2026-34516
AIOHTTP: Multipart Header Size Bypass
- State
- Published
- Severity
- 6.6 Medium
- Published
- Apr 1, 2026
- Updated
- Apr 4, 2026
- Reserved
- Mar 30, 2026
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.6 Medium | 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 | GitHub_M |
| 3.1 | 7.5 High | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H | CISA-ADP |
Weaknesses
- CWE-770 Allocation of Resources Without Limits or Throttling
Affected Products
| Product | Versions |
|---|---|
aiohttpaio-libs |
|
References
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