CVE-2026-34513Low▾ SunlitAIOHTTP Affected by Denial of Service (DoS) via Unbounded DNS Cache in TCPConnector
▾ Sunlit zone — Low / medium · no exploitation signal
impact 13.8 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Jul 13.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via OSV
0.4%
Last analysed / modified upstream
An unbounded DNS cache could result in excessive memory usage possibly resulting in a DoS situation.
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
aiohttp < 3.13.4Upgrade to a patched release:
aiohttp 3.13.4Connected by shared product, vendor, weakness, or advisory.
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