Is CVE-2026-47265 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-47265 being exploited in the wild.

How severe is CVE-2026-47265?

Medium severity, with a CVSS score of 4, published 2 June 2026.

Which products and versions are affected?

aiohttp (PyPI) < 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.0.

Is there a fix for CVE-2026-47265?

Yes. aiohttp (PyPI): upgrade to 3.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-47265 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-47265?

Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47265: AIOHTTP sensitive cookie leak during cross-origin redirect

Q: Which products and versions are affected?

aiohttp (PyPI) < 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.0.

Q: Is there a fix for CVE-2026-47265?

Yes. aiohttp (PyPI): upgrade to 3.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-47265 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-47265?

Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-47265 · Severity: medium · CVSS 4 · Published 2026-06-02

AIOHTTP is a popular Python library used by developers to build web servers and clients. A security flaw in the library's client component causes sensitive session cookies to be sent to unintended third-party websites during a redirect. If an attacker can trick an application into following a redirect to a malicious server, they could steal authentication tokens or other private user data.

Technologies: aiohttp (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-47265 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-47265 being exploited in the wild.
How severe is CVE-2026-47265?: Medium severity, with a CVSS score of 4, published 2 June 2026.
Which products and versions are affected?: aiohttp (PyPI) < 3.14.0, ECOSYSTEM:introduced=0,fixed=3.14.0.
Is there a fix for CVE-2026-47265?: Yes. aiohttp (PyPI): upgrade to 3.14.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-47265 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-47265?: Check whether you run aiohttp (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

aiohttp (PyPI): upgrade to 3.14.0 or later
```
pip install "aiohttp>=3.14.0"
```

Technical details

AIOHTTP fails to properly validate the origin before forwarding cookies during an HTTP redirect. When a request is initiated using the 'cookies' parameter, the library persists these cookies even if the server responds with a redirect to a different domain (cross-origin). An attacker who can control the destination of a redirect can capture these cookies, which may contain sensitive session identifiers or authentication tokens. This issue is rooted in the client-side request handling logic within 'aiohttp/client.py'. The vulnerability is addressed in version 3.14.0 by ensuring per-request cookies are dropped upon cross-origin redirection.

Affected products

aio-libs aiohttp < 3.14.0

Identifiers

CVE-2026-47265
GHSA-hg6j-4rv6-33pg
PYSEC-2026-2105

Timeline

2026-06-02: disclosed
2026-06-02: patched
2026-06-03: advisory

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.