GHSA-hcc4-c3v8-rx92

AIOHTTP Affected by Denial of Service (DoS) via Unbounded DNS Cache in TCPConnector

Source: GitHub Advisory Database (reviewed) Low CVE-2026-34513

Packages

Ecosystem	Package	Affected	Fixed in
PyPI	aiohttp	< 3.13.4	3.13.4

Details

As written in the advisory (Markdown source, shown as plain text).

### Summary An unbounded DNS cache could result in excessive memory usage possibly resulting in a DoS situation. ### Impact If an application makes requests to a very large number of hosts, this could cause the DNS cache to continue growing and slowly use excessive amounts of memory. ----- Patch: https://github.com/aio-libs/aiohttp/commit/c4d77c3533122be353b8afca8e8675e3b4cbda98

References

External links from the advisory. They lead to third-party sites.

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-hcc4-c3v8-rx92 web
https://nvd.nist.gov/vuln/detail/CVE-2026-34513 advisory
https://github.com/aio-libs/aiohttp/commit/c4d77c3533122be353b8afca8e8675e3b4cbda98 web
https://github.com/aio-libs/aiohttp package
https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4 web