CVE-2026-105829 (GCVE-0-2026-105829)

Vulnerability from cvelistv5 – Published: 2026-10-08 14:10 – Updated: 2026-10-10 03:05
VLAI
Title
League CommonMark 1.3.0 before 2.10.2 Stored XSS via DisallowedRawHtml Bypass
Summary
League CommonMark from 1.3.0 before 2.10.2 contains a cross-site scripting vulnerability that allows users posting Markdown to bypass the DisallowedRawHtml extension by ending raw HTML with a bare disallowed tag name. Attackers can place a lone <script or <iframe line followed by a block supplying attributes like src or onload, executing stored scripts in viewers' browsers under default GFM settings.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
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 2026-10-10 03:05 UTC
CWE
  • CWE-80 - Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6106 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
thephpleague commonmark     cpe:2.3:a:thephpleague:commonmark:-:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-21 00:00
Credits
4n86rakam1
Show details on NVD website
To clipboard 

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