CVE-2026-47265

Summary

Cookies set with the cookies parameter on requests are sent after following a cross-origin redirect.

Impact

If a developer uses the cookies parameter on a per-request basis then sensitive data might be leaked to an attacker if they manage to control a redirect.

Workaround

If unable to upgrade, using a Cookie header in the headers parameter is not vulnerable.

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Patch: https://github.com/aio-libs/aiohttp/commit/f54c40851b0d6c4bbdab97ba518a223adda32478