CVE-2026-34518CWE-200

AIOHTTP: Cookie and Proxy-Authorization headers leaked on cross-origin redirect

Low · published April 1, 2026

CVSS v4.0
2.7
EPSS
0%
Percentile
33.7
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
2.7 · LOW
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U
EPSS
0.00405 · 33.7th percentile
Weakness
CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
Published
2026-04-01T20:15Z
EPSS history
Timeline
  • 01 APR 20:15Z
    AIOHTTP: Cookie and Proxy-Authorization headers leaked on cross-origin redirect
    cvelistv5