CVE-2026-34513
AIOHTTP: Denial of Service (DoS) via Unbounded DNS Cache in TCPConnector
Description
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.
INFO
Published Date :
April 1, 2026, 9:16 p.m.
Last Modified :
April 15, 2026, 2:16 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 4.0 | LOW | [email protected] |
Solution
- Update AIOHTTP to version 3.13.4.
- Monitor memory usage after update.
- Apply vendor patches promptly.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-34513.
| URL | Resource |
|---|---|
| https://github.com/aio-libs/aiohttp/commit/c4d77c3533122be353b8afca8e8675e3b4cbda98 | Patch |
| https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 | Release Notes |
| https://github.com/aio-libs/aiohttp/security/advisories/GHSA-hcc4-c3v8-rx92 | Patch Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-34513 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-34513
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-34513 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-34513 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:aiohttp:aiohttp:*:*:*:*:*:*:*:* versions up to (excluding) 3.13.4 Added Reference Type GitHub, Inc.: https://github.com/aio-libs/aiohttp/commit/c4d77c3533122be353b8afca8e8675e3b4cbda98 Types: Patch Added Reference Type GitHub, Inc.: https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/aio-libs/aiohttp/security/advisories/GHSA-hcc4-c3v8-rx92 Types: Patch, Vendor Advisory -
New CVE Received by [email protected]
Apr. 01, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-770 Added Reference https://github.com/aio-libs/aiohttp/commit/c4d77c3533122be353b8afca8e8675e3b4cbda98 Added Reference https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 Added Reference https://github.com/aio-libs/aiohttp/security/advisories/GHSA-hcc4-c3v8-rx92