Authorization Header Exposure in AIOHTTP Framework
CVE-2026-34518

2.7LOW

Key Information:

Vendor

Aio-libs

Status
Aiohttp
Vendor
CVE Published:
1 April 2026

What is CVE-2026-34518?

A vulnerability exists in the AIOHTTP framework for asyncio and Python that affects the handling of Authorization headers during redirects to different origins. Versions prior to 3.13.4 drop the Authorization header while still retaining Cookie and Proxy-Authorization headers. This misbehavior could lead to unauthorized access to sensitive information, which has been addressed in the patched version 3.13.4.

Affected Version(s)

aiohttp < 3.13.4

References

https://github.com/aio-libs/aiohttp/security/advisories/G...
x_refsource_CONFIRM
https://github.com/aio-libs/aiohttp/commit/5351c980dcec7a...
x_refsource_MISC
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4
x_refsource_MISC

CVSS V4

Score:
2.7
Severity:
LOW
Confidentiality:
Low
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • Vulnerability published

  • Vulnerability Reserved

.