CVE-2026-105829

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.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/thephpleague/commonmark/security/advisories/GHSA-97jj-33gv-5xf9
https://www.vulncheck.com/advisories/league-commonmark-1.3.0-before-2.10.2-stored-xss-via-disallowedrawhtml-bypass
https://github.com/thephpleague/commonmark/security/advisories/GHSA-97jj-33gv-5xf9

Configurations

No configuration.

History

10 Oct 2026, 04:18

Type	Values Removed	Values Added
References	~~() https://github.com/thephpleague/commonmark/security/advisories/GHSA-97jj-33gv-5xf9 -~~	() https://github.com/thephpleague/commonmark/security/advisories/GHSA-97jj-33gv-5xf9 -

08 Oct 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 15:17

Updated : 2026-10-10 04:18

NVD link : CVE-2026-105829

Mitre link : CVE-2026-105829

CVE.ORG link : CVE-2026-105829

JSON object : View

Products Affected

No product.

CWE

CWE-80

Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

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