CVE-2026-47265: AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python

Q: How do I fix CVE-2026-47265?

aiohttp: upgrade to 3.14.0. Exact commands for each OS are on this page.

Q: Is CVE-2026-47265 being exploited?

CVE-2026-47265 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

Q: What does CVE-2026-47265 affect?

CVE-2026-47265 affects aiohttp. Severity is high (CVSS 7.5). AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.14.0, cookies set with the `cookies` parameter on requests are sent after following a cross-origin redirect. If a developer uses the `cookies

Q: How urgent is CVE-2026-47265?

Priority 32/100. High severity; Remotely exploitable, no login, no user action

Routine

HIGH 7.5REMOTEUPGRADE

CVE-2026-47265 is a high-severity flaw (CVSS 7.5) affecting aiohttp. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.14.0, cookies set with the `cookies` parameter on requests are sent after following a cross-origin redirect. 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. Version 3.14.0 patches the issue. If unable to upgrade, using a `Cookie` header in the

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.1% (top 96%)
CISA exploited list	No
Weakness	CWE-346
Published	2026-06-02
Last modified	2026-07-21

Publisher (CNA): GitHub, Inc. · Vendor: aiohttp

Last updated 2026-07-21 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2026-06-02 20:16 UTCPublished CVE record published
2026-07-21 19:10 UTCUpdated Record last modified

aiohttp aiohttp UPGRADE

Affected: < 3.14.0

Fixed in: 3.14.0

Safe to downgrade to: no unaffected older release

1. Check installed version

apt-cache policy aiohttp || rpm -q aiohttp || aiohttp --version

2. UPGRADE to 3.14.0 (Debian / Ubuntu)

sudo apt update && sudo apt install --only-upgrade aiohttp

2. UPGRADE (RHEL / Amazon Linux / Fedora)

sudo dnf upgrade aiohttp

Note

Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-47265?

aiohttp: upgrade to 3.14.0. Exact commands for each OS are on this page.

Is CVE-2026-47265 being exploited?

CVE-2026-47265 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-47265 affect?

CVE-2026-47265 affects aiohttp. Severity is high (CVSS 7.5). AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.14.0, cookies set with the `cookies` parameter on requests are sent after following a cross-origin redirect. If a developer uses the `cookies

How urgent is CVE-2026-47265?

Priority 32/100. High severity; Remotely exploitable, no login, no user action

Software pages

Python vulnerabilities

Related CVEs

CVE-2026-34514 MEDIUM 5.3 UPGRADE AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python
CVE-2026-34520 CRITICAL 9.1 UPGRADE AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python
CVE-2026-34517 MEDIUM 5.3 UPGRADE AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python
CVE-2026-34518 MEDIUM 5.3 UPGRADE AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python
CVE-2026-34519 MEDIUM 5.3 UPGRADE AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python

References

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