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CVE

CVE-2026-34520

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python.
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CVE

CVE-2026-34520

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python.

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.

Package Versions Affected

Package Version
patch Availability
No items found.

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CVSS Version

Severity
Base Score
CVSS Version
Score Vector
C
H
U
2.7
-
4.0
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/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
C
H
U
0
-
C
H
U
-

Related Resources

No items found.

References

https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4, https://github.com/aio-libs/aiohttp/commit/9370b9714a7a56003cacd31a9b4ae16eab109ba4, https://github.com/aio-libs/aiohttp/security/advisories/GHSA-63hf-3vf5-4wqf

Severity

9.1

CVSS Score
0
10

Basic Information

Base CVSS
9.1
EPSS Probability
0.00461%
EPSS Percentile
0.38104%
Introduced Version
0
Fix Available
3.13.4

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