Vulnerability · Published Apr 1, 2026 · Assigned by GitHub_M

CVE-2026-22815AIOHTTP: Uncapped memory usage possible through aiohttp allowing unlimited trailer headers

High 7.5

In plain English

A high-severity uncontrolled resource consumption in aiohttp from aio-libs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 60.2% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

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.

Affected packages & fixed versions

EcosystemPackageFixed inAdvisory
Alpine:v3.23py3-aiohttp3.13.5-r0ALPINE-CVE-2026-22815
Alpine:v3.24py3-aiohttp3.13.5-r0ALPINE-CVE-2026-22815
Debian:12python-aiohttp3.8.4-1+deb12u2DEBIAN-CVE-2026-22815
Debian:13python-aiohttpno fix listedDEBIAN-CVE-2026-22815
Debian:14python-aiohttp3.13.5-1DEBIAN-CVE-2026-22815
PyPIaiohttp3.13.4PYSEC-2026-2094
PyPIaiohttp3.13.4GHSA-w2fm-2cpv-w7v5
Ubuntu:25.10python-aiohttpno fix listedUBUNTU-CVE-2026-22815
Ubuntu:26.10python-aiohttpno fix listedUBUNTU-CVE-2026-22815

Affected products (as reported)

VendorProductVersions
aio-libs aiohttp < 3.13.4

Weakness: CWE-400, CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References