Description
AnyIO is a high level asynchronous concurrency and networking framework that works on top of either Trio or asyncio. Prior to 4.14.2, connect_tcp() and TLSStream.wrap() can validate internationalized host names after the standard library converts them with IDNA 2003 instead of IDNA 2008. When a connection to a non-ASCII domain is hijacked or redirected, an attacker can obtain a legitimate certificate for the different ASCII hostname produced by IDNA 2003 and present it to the client, causing the malicious endpoint's certificate to validate. This issue is fixed in version 4.14.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| agronholm | anyio | < 4.14.2 | — |
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-anyio | 4.15.1-1 | — |
| Debian 13 | python-anyio | No fix yet | — |
| Debian 12 | python-anyio | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | python-anyio | No fix yet | — |
| Ubuntu 26.04 LTS | python-anyio | No fix yet | — |
| Ubuntu 24.04 LTS | python-anyio | No fix yet | — |
| Ubuntu 22.04 LTS | python-anyio | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP6 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES 15 SP5 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES 15 SP4 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES 3 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
Show 8 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | python-anyio | 4.8.0-160000.3.1 | SUSE-SU-2026:24208-1 |
| SLES for SAP 15 SP6 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES for SAP 15 SP5 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES for SAP 15 SP4 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLES 16.0 | python-anyio | 4.8.0-160000.3.1 | SUSE-SU-2026:24208-1 |
| SLE Micro 6.2 | python-anyio | 4.8.0-160000.3.1 | SUSE-SU-2026:24122-1 |
| SLE HPC 15 SP5 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
| SLE HPC 15 SP4 | python-anyio | 4.1.0-150400.9.11.1 | SUSE-SU-2026:4416-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | graphifyy | 0.9.97-1.1 | openSUSE-SU-2026:12324-1 |
| openSUSE Leap 16.0 | python-anyio | 4.8.0-160000.3.1 | openSUSE-SU-2026:22060-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | kserve-storage-controller | 0.20.0-r9 | — |
| Wolfi rolling | open-webui | 0.11.3-r7 | — |
| Wolfi rolling | py3.14-anyio | 4.15.1-r1 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | anyio | < 4.14.2 | 4.14.2 | GHSA-82r6-8w77-94w6 |
Advisories 6
- WID-SEC-2026-4111 Red Hat Ansible Automation Platform: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- openSUSE-SU-2026:12324-1 graphifyy-0.9.97-1.1 on GA media SUSE / openSUSE Security Updates · Oct 29, 2026
- SUSE-SU-2026:24208-1 Security update for python-anyio SUSE / openSUSE Security Updates · Oct 21, 2026
- openSUSE-SU-2026:22060-1 Security update for python-anyio SUSE / openSUSE Security Updates · Oct 19, 2026
- SUSE-SU-2026:24122-1 Security update for python-anyio SUSE / openSUSE Security Updates · Oct 13, 2026
- SUSE-SU-2026:4416-1 Security update for python-anyio SUSE / openSUSE Security Updates · Oct 2, 2026