aiohttp allows unlimited trailer headers, leading to possible uncapped memory usage
Summary
Insufficient restrictions in header/trailer handling could cause uncapped memory usage.
Impact
An application could cause memory exhaustion when receiving an attacker controlled request or response. A vulnerable web application could mitigate these risks with a typical reverse proxy configuration.
Patch: https://github.com/aio-libs/aiohttp/commit/0c2e9da51126238a421568eb7c5b53e5b5d17b36
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | aiohttp | < 3.13.4 | 3.13.4 |
References
- https://github.com/aio-libs/aiohttp/releases/tag/v3.13.4
- https://github.com/aio-libs/aiohttp/commit/0c2e9da51126238a421568eb7c5b53e5b5d17b36
- https://github.com/aio-libs/aiohttp/security/advisories/GHSA-w2fm-2cpv-w7v5
- https://nvd.nist.gov/vuln/detail/CVE-2026-22815
- https://github.com/aio-libs/aiohttp
- CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N- Weakness (CWE)
CWE-400, CWE-770- Platform
- Python (PyPI)
- Package
aiohttp- Disclosed
- 01.04.2026
- Updated
- 11.10.2026 15:17
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2026-2094 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-w2fm-2cpv-w7v5 - 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.
- 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
- 2021: 1
- 2022: 0
- 2023: 6
- 2024: 7
- 2025: 1
- 2026: 40
-
aiohttp allows unlimited trailer headers, leading to possible uncapped memory usage this entry
Know which vulnerabilities affect your application
With the DockRay integration and software inventory enabled, DockRay checks reported component versions against known vulnerabilities and notifies you about confirmed matches. Coverage depends on the supported technology and available advisory data.