CVE-2026-34520 (GCVE-0-2026-34520)
Vulnerability from cvelistv5
Published
2026-04-01 20:27
Modified
2026-04-04 03:13
Severity ?
2.7 (Low) - CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U
CWE
  • CWE-113 - Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')
Summary
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.
References
Impacted products
Vendor Product Version
aio-libs aiohttp Version: < 3.13.4
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