CVE-2026-48801

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/markdown-it/linkify-it/commit/6be6d15e0641bf1daeaa977d500cabc743166159	Patch
https://github.com/markdown-it/linkify-it/security/advisories/GHSA-22p9-wv53-3rq4	Exploit Vendor Advisory
https://github.com/markdown-it/linkify-it/security/advisories/GHSA-22p9-wv53-3rq4	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:markdown-it:linkify-it:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-07-14 21:17

Updated : 2026-08-06 18:23

NVD link : CVE-2026-48801

Mitre link : CVE-2026-48801

CVE.ORG link : CVE-2026-48801

JSON object : View

Products Affected

markdown-it

linkify-it

CWE

CWE-1333

Inefficient Regular Expression Complexity

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