CVE-2026-34993

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.14.0, using ``CookieJar.load()`` with untrusted input may allow arbitrary code execution. Most applications using this function will be doing so with the user's own data, so this is unlikely to affect many applications. Version 3.14.0 patches the issue. If an application does allow attacker controlled files to be loaded, a workaround on older releases would be to sanitize the files before loading.

What this means for your business

It affects Aiohttp. It matters if your company, or a supplier that handles your data, runs it.
An attacker can use it only with access to the machine itself, with an administrator login, but only after tricking someone into an action such as opening a file or a link.
FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 7% of all known flaws.

What to do

1Check whether your company or your suppliers run Aiohttp, and which version. The affected versions are listed further down this page.
2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

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Scoring

CVSS: 6.4 (v3.1)
Vector: CVSS:3.1/AV:L/AC:H/PR:H/UI:R/S:C/C:L/I:H/A:L
Weakness: CWE-502
Assigned by: security-advisories@github.com

Dates

Published: 2026-06-02
Last modified: 2026-09-04
Sources: NVD

Affected products

Aiohttp Aiohttp- 3.14.0

As listed in the NVD configuration data. Not a statement about your estate.