CVE-2026-63670 (GCVE-0-2026-63670)

Vulnerability from cvelistv5 – Published: 2026-08-17 19:49 – Updated: 2026-08-18 18:08
VLAI
Title
ApostropheCMS: Mutation-XSS / allowedTags bypass via literal `</textarea/>` solidus close
Summary
ApostropheCMS is an open-source Node.js content management system. Prior to 2.17.6, sanitizeHtml() can pass disallowed executable markup through packages/sanitize-html/index.js when textarea or xmp is included in allowedTags because a literal solidus after the raw-text end-tag name is treated as text by htmlparser2 and the ontext handler emits that content without escaping, while a browser parses the following img onerror markup as active HTML. This issue is fixed in version 2.17.6.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-18 18:07 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7895 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
apostrophecms apostrophe Affected: < 2.17.6
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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