Fluid Attacks Database

Description

AIOHTTP leaks Cookie and Proxy-Authorization headers on cross-origin redirect

Summary

When following redirects to a different origin, aiohttp drops the Authorization header, but retains the Cookie and Proxy-Authorization headers.

Impact

The Cookie and Proxy-Authorizations headers could contain sensitive information which may be leaked to an unintended party after following a redirect.

Patch: https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb6

Mitigation

Update Impact

Minimal update. May introduce new vulnerabilities or breaking changes.

Ecosystem	Package	Affected version	Patched versions
pypi	aiohttp	>=0 <3.13.4	3.13.4
debian 14	python-aiohttp	=3.11.16-1 \|\| =3.12.15-1 \|\| =3.13.0-1 \|\| =3.13.1-1 \|\| =3.13.3-1 \|\| =3.13.3-2 \|\| =3.13.3-3 \|\| >=0 <3.13.5-1	3.13.5-1
debian 11	python-aiohttp	=3.7.4-1 \|\| =3.7.4-1+deb11u1 \|\| >=0 <3.7.4-1+deb11u2	3.7.4-1+deb11u2
debian 13	python-aiohttp	=3.11.16-1 \|\| =3.11.16-1+deb13u1 \|\| =3.12.15-1 \|\| =3.13.0-1 \|\| =3.13.1-1 \|\| =3.13.3-1 \|\| =3.13.3-2 \|\| =3.13.3-3 \|\| =3.13.5-1	-
debian 12	python-aiohttp	=3.10.0-1 \|\| =3.10.1-1 \|\| =3.10.10-1 \|\| =3.10.10-2 \|\| =3.10.11-1 \|\| =3.10.3-1 \|\| =3.10.3-2 \|\| =3.10.3-3 \|\| =3.10.4-1 \|\| =3.10.5-1 \|\| =3.10.6-1 \|\| =3.10.8-1 \|\| =3.11.15-1 \|\| =3.11.16-1 \|\| =3.12.15-1 \|\| =3.13.0-1 \|\| =3.13.1-1 \|\| =3.13.3-1 \|\| =3.13.3-2 \|\| =3.13.3-3 \|\| =3.13.5-1 \|\| =3.8.4-1 \|\| =3.8.4-1+deb12u1 \|\| =3.8.5-1 \|\| =3.8.6-1 \|\| =3.9.1-1 \|\| =3.9.5-1	-

Aliases

1. CVE-2026-345182. NVD-2026-345183. OSV-2026-345184. OSV-DEBIAN-2026-345185. GHSA-966j-vmvw-g2g96. GCVE-2026-345187. SECURITY-TRACKER-CVE-2026-34518

References

1. https://github.com/aio-libs/aiohttp/security/advisories/GHSA-966j-vmvw-g2g92. https://github.com/aio-libs/aiohttp/commit/5351c980dcec7ad385730efdf4e1f4338b24fdb63. https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4

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