Description
AIOHTTP is an asynchronous HTTP client/server framework for asyncio and Python. Prior to version 3.13.4, an attacker who controls the reason parameter when creating a Response may be able to inject extra headers or similar exploits. This issue has been patched in version 3.13.4.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| aio-libs | aiohttp | < 3.13.4 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | python-aiohttp | 3.13.5-1 | — |
| Debian 13 | python-aiohttp | No fix yet | — |
| Debian 12 | python-aiohttp | 3.8.4-1+deb12u2 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | python-aiohttp | No fix yet | — |
| Ubuntu 25.10 | python-aiohttp | No fix yet | — |
Show 6 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | python-aiohttp | No fix yet | — |
| Ubuntu Pro 24.04 LTS | python-aiohttp | No fix yet | — |
| Ubuntu Pro 22.04 LTS | python-aiohttp | No fix yet | — |
| Ubuntu Pro 20.04 LTS | python-aiohttp | No fix yet | — |
| Ubuntu Pro 18.04 LTS | python-aiohttp | No fix yet | — |
| Ubuntu Pro 16.04 LTS | python-aiohttp | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | python-aiohttp | 3.6.0-150100.3.35.1 | SUSE-SU-2026:3059-1 |
| SLES 15 SP6 | python-aiohttp | 3.6.0-150100.3.35.1 | SUSE-SU-2026:3207-1, SUSE-SU-2026:3059-1 |
| SLES 15 SP5 | python-aiohttp | 3.6.0-150100.3.35.1 | SUSE-SU-2026:3207-1, SUSE-SU-2026:3059-1 |
| SLES 15 SP4 | python-aiohttp | 3.6.0-150100.3.35.1 | SUSE-SU-2026:3207-1, SUSE-SU-2026:3059-1 |
| SLES 3 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | python-aiohttp | 3.11.16-160000.5.1 | SUSE-SU-2026:22173-1 |
| SLES for SAP 15 SP6 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
| SLES for SAP 15 SP5 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
| SLES for SAP 15 SP4 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
| SLES 16.0 | python-aiohttp | 3.11.16-160000.5.1 | SUSE-SU-2026:22173-1 |
| SLE HPC 15 SP5 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
| SLE HPC 15 SP4 | python-aiohttp | 3.9.3-150400.10.43.1 | SUSE-SU-2026:3207-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | python-aiohttp | 3.11.16-160000.5.1 | openSUSE-SU-2026:21098-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.24 | py3-aiohttp | 3.13.5-r0 | — |
| Alpine v3.23 | py3-aiohttp | 3.13.5-r0 | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-aiohttp | No fix yet | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 9 | python39-oci-sdk +1 | 2.187.0-1.0.5.el9 | ELSA-2026-604898 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | airflow-3 | 3.1.8-r11 | — |
| Wolfi rolling | checkov | 3.2.517-r0 | — |
| Wolfi rolling | dask-kubernetes | 2026.3.0-r3 | — |
| Wolfi rolling | kserve-storage-controller | 0.17.0-r2 | — |
| Wolfi rolling | kubeflow-pipelines-visualization-server | 2.16.0-r4 | — |
| Wolfi rolling | open-webui | 0.8.12-r3 | — |
| Wolfi rolling | py3-cassandra-medusa | 0.27.1-r2 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | aiohttp | < 3.13.4 | 3.13.4 | GHSA-mwh4-6h8g-pg8w |
Advisories 6
- WID-SEC-2026-2933 Splunk SOAR: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 2, 2026
- ELSA-2026-604898 Important: python-oci-sdk security update (Oracle Linux 9) Oracle Linux Security Advisories (ELSA) · Oct 21, 2026
- SUSE-SU-2026:3207-1 Security update for python-aiohttp SUSE / openSUSE Security Updates · Jul 24, 2026
- SUSE-SU-2026:3059-1 Security update for python-aiohttp SUSE / openSUSE Security Updates · Jul 16, 2026
- openSUSE-SU-2026:21098-1 Security update for python-aiohttp SUSE / openSUSE Security Updates · Jun 30, 2026
- SUSE-SU-2026:22173-1 Security update for python-aiohttp SUSE / openSUSE Security Updates · Jun 24, 2026