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PYSEC-2026-1100

AIOHTTP vulnerable to denial of service through large payloads

Quick fix

PYSEC-2026-1100 — aiohttp: upgrade to the fixed version with the command below.

pip install --upgrade 'aiohttp>=3.13.3'

Details

### Summary A request can be crafted in such a way that an aiohttp server's memory fills up uncontrollably during processing.

### Impact If an application includes a handler that uses the `Request.post()` method, an attacker may be able to freeze the server by exhausting the memory.

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Patch: https://github.com/aio-libs/aiohttp/commit/b7dbd35375aedbcd712cbae8ad513d56d11cce60

Are you affected?

Enter the version of the package you're using.

Affected packages

PyPI/aiohttp

Introduced in: 0Fixed in: 3.13.3

Fixpip install --upgrade 'aiohttp>=3.13.3'

References

https://github.com/aio-libs/aiohttp/security/advisories/GHSA-6jhg-hg63-jvvf[WEB]
https://nvd.nist.gov/vuln/detail/CVE-2025-69228[ADVISORY]
https://github.com/aio-libs/aiohttp/commit/b7dbd35375aedbcd712cbae8ad513d56d11cce60[FIX]
https://github.com/aio-libs/aiohttp[PACKAGE]
https://pypi.org/project/aiohttp[PACKAGE]
https://github.com/advisories/GHSA-6jhg-hg63-jvvf[ADVISORY]