CVE-2026-34513
Unbounded DNS Cache in AIOHTTP Causes Memory DoS
Publication date: 2026-04-01
Last updated on: 2026-04-15
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| aiohttp | aiohttp | to 3.13.4 (exc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-770 | The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability in AIOHTTP, an asynchronous HTTP client/server framework for asyncio and Python, involves an unbounded DNS cache prior to version 3.13.4. This means that the DNS cache could grow without limits, leading to excessive memory usage.
Such uncontrolled memory consumption could potentially cause a denial of service (DoS) situation by exhausting system resources.
This issue has been fixed in version 3.13.4 of AIOHTTP.
How can this vulnerability impact me? :
This vulnerability can impact you by causing excessive memory usage in applications using affected versions of AIOHTTP.
The unbounded DNS cache can lead to resource exhaustion, which may result in a denial of service (DoS) condition where the application or system becomes unresponsive or crashes.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, you should upgrade AIOHTTP to version 3.13.4 or later, where the unbounded DNS cache issue has been patched.