aio-libs aiohttp up to 3.13.3 Parameter content_type response splitting

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k1.50-

Summaryinfo

A vulnerability was found in aio-libs aiohttp up to 3.13.3. It has been declared as problematic. Affected by this vulnerability is an unknown functionality of the component Parameter Handler. Such manipulation of the argument content_type leads to response splitting. This vulnerability is traded as CVE-2026-34514. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in aio-libs aiohttp up to 3.13.3 and classified as problematic. Affected by this issue is some unknown processing of the component Parameter Handler. The manipulation of the argument content_type with an unknown input leads to a response splitting vulnerability. Using CWE to declare the problem leads to CWE-113. The product receives data from an HTTP agent/component (e.g., web server, proxy, browser, etc.), but it does not neutralize or incorrectly neutralizes CR and LF characters before the data is included in outgoing HTTP headers. Impacted is integrity. CVE summarizes:

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the content_type parameter in aiohttp could use this to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-34514 since 03/30/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

Upgrading to version 3.13.4 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch 9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Response splitting
CWE: CWE-113 / CWE-93 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: aiohttp 3.13.4
Patch: 9a6ada97e2c6cf1ce31727c6c9fcea17c21f6f06

Timelineinfo

03/30/2026 CVE reserved
04/02/2026 +3 days Advisory disclosed
04/02/2026 +0 days VulDB entry created
04/02/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: GHSA-2vrm-gr82-f7m5
Status: Confirmed

CVE: CVE-2026-34514 (🔒)
GCVE (CVE): GCVE-0-2026-34514
GCVE (VulDB): GCVE-100-354794

Entryinfo

Created: 04/02/2026 02:39
Changes: 04/02/2026 02:39 (72)
Complete: 🔍
Cache ID: 216:674:103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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