CVE-2026-34518

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, when following redirects to a different origin, aiohttp drops the Authorization header, but retains the Cookie and Proxy-Authorization headers. This issue has been patched in version 3.13.4.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6	Patch
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4	Release Notes
https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g9	Patch Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:*

History

16 Apr 2026, 16:35

Type	Values Removed	Values Added
References	~~() https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6 -~~	() https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6 - Patch
References	~~() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 -~~	() https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 - Release Notes
References	~~() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g9 -~~	() https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g9 - Patch, Vendor Advisory
CPE		cpe:2.3:a:aiohttp:aiohttp::::::::
First Time		Aiohttp aiohttp Aiohttp
CWE		NVD-CWE-noinfo
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3

01 Apr 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-01 21:17

Updated : 2026-04-16 16:35

NVD link : CVE-2026-34518

Mitre link : CVE-2026-34518

CVE.ORG link : CVE-2026-34518

JSON object : View

Products Affected

aiohttp

aiohttp

CWE

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

NVD-CWE-noinfo

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