CVE-2026-13676

node-ajv: fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs

CVE-2026-13676 is fixed in 8 products on 1 platform, first by DEBIAN-CVE-2026-13676, released June 29, 2026. It is not reported as exploited. Patch Radar priority: High.

High
CVSS
7.5
high
Exploitation
None reported
No vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.0069
53rd percentile

fast-uri versions 2.3.1 through 3.1.2 and 4.0.0 fail to canonicalize Unicode (IDN) hostnames for HTTP-family URLs. The IDN conversion path calls a helper that does not exist on the global URL constructor, silently leaving the host in its original Unicode form while normalize() and equal() still return values that differ from a WHATWG-compatible URL parser. Applications that use fast-uri to enforce host-based policy (denylists, loopback filtering, redirect validation, outbound proxy routing) before passing the same URL to Node's URL or fetch can be bypassed when the two implementations resolve the same input to different hosts. Patches: upgrade to fast-uri 3.1.3 for the 3.x line or 4.0.1 for the 4.x line. Workarounds: enforce host policy using the same URL parser used for the actual request, or reject non-ASCII hosts before policy checks.

Where it's fixed

ProductFixed inFixReleased
Linux
agama-web-ui · opensuse-leap 16.0 17+673.b97ba64d6-160000.12.1 OPENSUSE-SU-2026:21448-1 Jul 27, 2026
node-ajv · Debian 14 8.20.0~ds+~cs7.1.2-1 DEBIAN-CVE-2026-13676 Jun 29, 2026
python-jupytext · Fedora 43 1.19.6-1.fc43 FEDORA-2026-3942AB86FD Oct 5, 2026
python-jupytext-doc · Fedora 43 1.19.6-1.fc43 FEDORA-2026-3942AB86FD Oct 5, 2026
python-pydata-sphinx-theme · opensuse-leap 16.0 0.16.1-bp160.3.1 OPENSUSE-SU-2026:21231-1 Jul 3, 2026
python3-jupyterlab-jupytext · Fedora 43 1.19.6-1.fc43 FEDORA-2026-3942AB86FD Oct 5, 2026
python3-jupytext · Fedora 43 1.19.6-1.fc43 FEDORA-2026-3942AB86FD Oct 5, 2026
rh-podman-desktop · RHEL 10 1.1.2-1.el10_2 RHSA-2026:57590 Aug 21, 2026

Patch Radar data is free to use with attribution. Terms and how to credit it.

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.