CVE-2026-34514 | aio-libs aiohttp up to 3.13.3 Parameter content_type response splitting (GHSA-2vrm-gr82-f7m5)

VDB-354794 · CVE-2026-34514 · GHSA-2VRM-GR82-F7M5 AIO-LIBS AIOHTTP UP TO 3.13.3 PARAMETER CONTENT_TYPE RESPONSE SPLITTING HISTORYDIFFRELATEJSONXMLCTI CVSS Meta Temp Score Current Exploit Price (≈) CTI Interest Score 5.1 $0-$5k 1.60+ 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. Productinfo Vendor aio-libs Name aiohttp Version 3.13.0 3.13.1 3.13.2 3.13.3 License open-source Website Product: https://github.com/aio-libs/aiohttp/ 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 Vector Complexity Authentication Confidentiality Integrity Availability Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock Unlock 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: 🔒 0-Day Unlock Unlock Unlock Unlock Today Unlock Unlock Unlock Unlock 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: 99:A69:101 Discussion No comments yet. Languages: en. Please log in to comment. ◂ PreviousOverviewNext ▸