What is CVE-2026-54273?

CVE-2026-54273 is a high-severity vulnerability in Aiohttp, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-06-22.

How severe is CVE-2026-54273?

High severity. CVSS v3 base score is 7.5 out of 10.

Resource exhaustion in Aiohttp

CVE-2026-54273

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to 3.14.1, no limit was present on the number of pipelined requests that could be queued. An attacker may be able to use pipelined requests to use excess…

EPSS: 0.003 (20.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Aiohttp
Aio-libs Aiohttp — versions < 3.14.1

Weakness classification (CWE)

CWE-770 — Allocation of Resources Without Limits or Throttling

References

security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory)
security-advisories@github.com (Patch, x_refsource_MISC)

Frequently asked questions

What is CVE-2026-54273?: CVE-2026-54273 is a high-severity vulnerability in Aiohttp, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 7.5/10. Published 2026-06-22.
How severe is CVE-2026-54273?: High severity. CVSS v3 base score is 7.5 out of 10.