Resource exhaustion in Aiohttp

CVE-2026-22815

AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, insufficient restrictions in header/trailer handling could cause uncapped memory usage. This issue has been patched in version 3.13.4.

Vulnerability class: DoS (Denial of Service)

EPSS: 0.004 (35.8th 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

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-22815?
CVE-2026-22815 is a high-severity vulnerability in Aiohttp, classified under Uncontrolled Resource Consumption. CVSS score: 7.5/10. Published 2026-04-01.
How severe is CVE-2026-22815?
High severity. CVSS v3 base score is 7.5 out of 10.