CVE-2026-34993: CWE-502: Deserialization of Untrusted Data in aio-libs aiohttp
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.
AI Analysis
Technical Summary
The vulnerability CVE-2026-34993 in aiohttp, a Python asynchronous HTTP framework, arises from unsafe deserialization in the CookieJar.load() function when processing untrusted input. This can lead to arbitrary code execution if an attacker can supply crafted input files. The flaw is classified under CWE-502 (Deserialization of Untrusted Data). Exploitation requires local access with high privileges and user interaction, and the attack complexity is high. The issue is patched in aiohttp version 3.14.0. Applications that do not load attacker-controlled files are unlikely to be affected.
Potential Impact
If exploited, this vulnerability allows an attacker to execute arbitrary code on the affected system, potentially compromising confidentiality, integrity, and availability. However, exploitation requires local access with high privileges and user interaction, and the application must load untrusted input via CookieJar.load(). The impact is rated medium with CVSS 6.4 due to these constraints.
Mitigation Recommendations
A fix is available in aiohttp version 3.14.0. Users should upgrade to this version to remediate the vulnerability. For applications that cannot upgrade immediately but load untrusted files via CookieJar.load(), input sanitization before loading is recommended to prevent code execution. Most applications using CookieJar.load() with trusted data are not affected. No additional action is required if untrusted input is not loaded.
CVE-2026-34993: CWE-502: Deserialization of Untrusted Data in aio-libs aiohttp
Description
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.
CVSS v3.1
Score 6.4medium
Affected software
aio-libs
aiohttp
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-34993 in aiohttp, a Python asynchronous HTTP framework, arises from unsafe deserialization in the CookieJar.load() function when processing untrusted input. This can lead to arbitrary code execution if an attacker can supply crafted input files. The flaw is classified under CWE-502 (Deserialization of Untrusted Data). Exploitation requires local access with high privileges and user interaction, and the attack complexity is high. The issue is patched in aiohttp version 3.14.0. Applications that do not load attacker-controlled files are unlikely to be affected.
Potential Impact
If exploited, this vulnerability allows an attacker to execute arbitrary code on the affected system, potentially compromising confidentiality, integrity, and availability. However, exploitation requires local access with high privileges and user interaction, and the application must load untrusted input via CookieJar.load(). The impact is rated medium with CVSS 6.4 due to these constraints.
Mitigation Recommendations
A fix is available in aiohttp version 3.14.0. Users should upgrade to this version to remediate the vulnerability. For applications that cannot upgrade immediately but load untrusted files via CookieJar.load(), input sanitization before loading is recommended to prevent code execution. Most applications using CookieJar.load() with trusted data are not affected. No additional action is required if untrusted input is not loaded.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-03-31T19:38:31.618Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://access.redhat.com/security/cve/CVE-2026-34993","vendor":"Red Hat"},{"url":"https://access.redhat.com/errata/RHSA-2026:24977","vendor":"Red Hat"}]
Threat ID: 6a1f348ce29bf47b50fa1feb
Added to database: 06/02/2026, 19:52:44 UTC
Last enriched: 08/11/2026, 13:23:46 UTC
Last updated: 09/11/2026, 22:23:26 UTC
Views: 109
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