VULNERABILITY INTELLIGENCE
CVE-2026-34520
CVSS score9.1 CRITICAL
EPSS probability0.48%
CISA KEVNot currently listed
Published2026-04-01
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, the C parser (the default for most installs) accepted null bytes and control characters in response headers. This issue has been patched in version 3.13.4.
Weakness classification
- security-advisories@github.com: CWE-113
Primary references
- security-advisories@github.com — Patch
- security-advisories@github.com — Release Notes
- security-advisories@github.com — Patch, Vendor Advisory