CVE-2026-48801 (GCVE-0-2026-48801)

Vulnerability from cvelistv5 – Published: 2026-07-14 20:03 – Updated: 2026-07-15 12:56
VLAI
Title
linkify-it: Quadratic algorithmic complexity in LinkifyIt#match scan loop
Summary
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.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-15 12:56 UTC
CWE
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7926 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
markdown-it linkify-it Affected: < 5.0.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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