Medium

AIOHTTP vulnerable to denial of service through large payloads

  • Disclosed: 05.01.2026
  • Updated: 11.10.2026 15:17

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.


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

Affected software

Click a technology to see all vulnerabilities affecting it.

PlatformPackageVulnerable versionsFixed in
Python (PyPI) aiohttp < 3.13.3 3.13.3

References

CVSS score -
CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U
Weakness (CWE)
CWE-770
Platform
Python (PyPI)
Package
aiohttp
Disclosed
05.01.2026
Updated
11.10.2026 15:17

Sources and licenses

OSV / GitHub Advisory Database - PYSEC-2026-1100 - PyPA Advisory Database; CC BY 4.0

OSV / GitHub Advisory Database - GHSA-6jhg-hg63-jvvf - CC BY 4.0

Vulnerability history: aiohttp

All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.

All (55) in the archive
Total entries
55
First → latest
02.2021 10.2026
Without a fix
0
Exploited in attacks
0

Severity breakdown

  • High 7
  • Medium 29
  • Low 19

Disclosures per year

  1. 2021: 1
  2. 2022: 0
  3. 2023: 6
  4. 2024: 7
  5. 2025: 1
  6. 2026: 40
Severity:
  1. High CVE-2026-111066 >= 2.0.0, < 3.14.4 3.14.4
  2. High CVE-2026-111064 < 3.14.4 3.14.4
  3. AIOHTTP vulnerable to denial of service through large payloads this entry
    Medium CVE-2025-69228 < 3.13.3 3.13.3
  4. High · 5.9 CVE-2024-23334 >= 1.0.5, < 3.9.2 3.9.2

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