aio-libs aiohttp up to 3.13.3 DNS Cache allocation of resources

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.76-

Summaryinfo

A vulnerability was found in aio-libs aiohttp up to 3.13.3. It has been classified as problematic. Affected is an unknown function of the component DNS Cache Handler. This manipulation causes allocation of resources. This vulnerability appears as CVE-2026-34513. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in aio-libs aiohttp up to 3.13.3 and classified as problematic. Affected by this vulnerability is an unknown code block of the component DNS Cache Handler. The manipulation with an unknown input leads to a allocation of resources vulnerability. The CWE definition for the vulnerability is CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. As an impact it is known to affect availability. The summary by CVE is:

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an unbounded DNS cache could result in excessive memory usage possibly resulting in a DoS situation. This issue has been patched in version 3.13.4.

The advisory is shared at github.com. This vulnerability is known as CVE-2026-34513 since 03/30/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

Upgrading to version 3.13.4 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch c4d77c3533122be353b8afca8e8675e3b4cbda98 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.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Version

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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: Allocation of resources
CWE: CWE-770 / CWE-400 / CWE-404
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: c4d77c3533122be353b8afca8e8675e3b4cbda98

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-hcc4-c3v8-rx92
Status: Confirmed

CVE: CVE-2026-34513 (🔒)
GCVE (CVE): GCVE-0-2026-34513
GCVE (VulDB): GCVE-100-354793

Entryinfo

Created: 04/02/2026 02:39
Changes: 04/02/2026 02:39 (71)
Complete: 🔍
Cache ID: 216:17E:103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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