# CVE-2026-84292: node-ajv: fast-uri serializes the port component of a URI without validating it

CVE-2026-84292 is fixed in 6 products on 1 platform, first by DEBIAN-CVE-2026-84292, released September 10, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-84292
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0024
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 2, 2026

## Description

fast-uri serializes the port component of a URI without validating it. When recomposing the authority, the userinfo and host components are escaped but the port is concatenated verbatim, so a port value that is not a sequence of digits can inject authority delimiters, demoting the intended host to userinfo and pointing the authority at an attacker-controlled host. Both fast-uri and Node's URL read the result back as the attacker's host with no error, so re-validating the built URI does not catch it. This affects applications that build URIs from parts and assign untrusted data to the port component through the serialize, normalize, or equal functions in their object forms. The issue affects fast-uri versions before 2.4.6, from 3.0.0 before 3.1.7, and from 4.0.0 before 4.1.4. It is fixed in 2.4.6, 3.1.7, and 4.1.4, where recomposeAuthority rejects any port that is not a digit sequence per RFC 3986.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | cockpit-image-builder RHEL 10 | 94.4-1.el10_2 | [RHSA-2026:71543](https://patchblox.com/security/data/fix/linux/rhsa-2026-71543.md) | Sep 25, 2026 |
| Linux | cockpit-image-builder almalinux 10 | 94.4-1.el10_2 | [ALSA-2026:71543](https://patchblox.com/security/data/fix/linux/alsa-2026-71543.md) | Sep 24, 2026 |
| Linux | cockpit-image-builder ol 10 | 0:94.4-1.0.1.el10_2 | [ELSA-2026-71543](https://patchblox.com/security/data/fix/linux/elsa-2026-71543.md) | Sep 24, 2026 |
| Linux | cockpit-image-builder rocky 10 | 0:94.4-1.el10_2 | [RLSA-2026:71543](https://patchblox.com/security/data/fix/linux/rlsa-2026-71543.md) | Sep 25, 2026 |
| Linux | node-ajv Debian 14 | 8.20.0~ds+~cs7.1.5-1 | [DEBIAN-CVE-2026-84292](https://patchblox.com/security/data/fix/linux/debian-cve-2026-84292.md) | Sep 10, 2026 |
| Linux | python-jupytext Fedora 43 | 1.19.6-1.fc43 | [FEDORA-2026-3942AB86FD](https://patchblox.com/security/data/fix/linux/fedora-2026-3942ab86fd.md) | Oct 5, 2026 |
| Linux | python-jupytext-doc Fedora 43 | 1.19.6-1.fc43 | [FEDORA-2026-3942AB86FD](https://patchblox.com/security/data/fix/linux/fedora-2026-3942ab86fd.md) | Oct 5, 2026 |
| Linux | python3-jupyterlab-jupytext Fedora 43 | 1.19.6-1.fc43 | [FEDORA-2026-3942AB86FD](https://patchblox.com/security/data/fix/linux/fedora-2026-3942ab86fd.md) | Oct 5, 2026 |
| Linux | python3-jupytext Fedora 43 | 1.19.6-1.fc43 | [FEDORA-2026-3942AB86FD](https://patchblox.com/security/data/fix/linux/fedora-2026-3942ab86fd.md) | Oct 5, 2026 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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