# CVE-2026-48801: linkify-it: Quadratic algorithmic complexity in LinkifyIt#match scan loop

> CVE-2026-48801: linkify-it: Quadratic algorithmic complexity in LinkifyIt#match scan loop. CVSS 7.5 (CVSS 3.1).

Canonical: https://rewindex.com/cve/CVE-2026-48801
Last updated: 2026-10-24T21:10:00Z

- Published: 2026-07-14 20:03 UTC · Updated: 2026-10-24 21:10 UTC · Assigner: GitHub\_M
- CVSS: 7.5 (CVSS 3.1) · Severity: High · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS: 0.39%, 33th percentile (scored 2026-10-25)
- CISA KEV: no
- CWE: CWE-1333

## Description

linkify-it is a links recognition library with full Unicode support. Prior to 5.0.1, LinkifyIt.prototype.match, the package's primary public API, has O(N²) algorithmic complexity for inputs containing many fuzzy links or emails because the JavaScript-level scan loop re-slices input and re-runs unanchored regex searches on progressively shorter tails. Any service that synchronously renders untrusted Markdown with linkify:true on a request hot path can inherit a worker-process denial of service triggerable by a tens-of-KB request body. This issue is fixed in version 5.0.1.

## Affected vendors and products

- markdown-it: linkify-it

## Tracked companies

- [Confluence](https://rewindex.com/company/confluence.md)
- [Jira](https://rewindex.com/company/jira.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2026-48801)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2026-48801)
- [https://github.com/markdown-it/linkify-it/commit/6be6d15e0641bf1daeaa977d500cabc743166159](https://github.com/markdown-it/linkify-it/commit/6be6d15e0641bf1daeaa977d500cabc743166159)
- [https://github.com/markdown-it/linkify-it/security/advisories/GHSA-22p9-wv53-3rq4](https://github.com/markdown-it/linkify-it/security/advisories/GHSA-22p9-wv53-3rq4)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2026-48801 · Markdown: https://rewindex.com/cve/CVE-2026-48801.md · JSON: https://rewindex.com/api/v1/cves/CVE-2026-48801 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T02:05:18.724Z