CVE-2026-30838

Published: Mar 07, 2026 Last Modified: Mar 11, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 5,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: passive
Confidentiality: N/A
Integrity: N/A
Availability: N/A
MEDIUM 6,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: required
Scope: changed
Confidentiality: low
Integrity: low
Availability: none

Description

AI Translation Available

league/commonmark is a PHP Markdown parser. Prior to version 2.8.1, the DisallowedRawHtml extension can be bypassed by inserting a newline, tab, or other ASCII whitespace character between a disallowed HTML tag name and the closing >. For example, <script\n> would pass through unfiltered and be rendered as a valid HTML tag by browsers. This is a cross-site scripting (XSS) vector for any application that relies on this extension to sanitize untrusted user input. All applications using the DisallowedRawHtml extension to process untrusted markdown are affected. Applications that use a dedicated HTML sanitizer (such as HTML Purifier) on the rendered output are not affected. This issue has been patched in version 2.8.1.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0005
Percentile
0,1th
Updated

EPSS Score Trend (Last 8 Days)

79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Access Control Confidentiality Integrity Availability
Potential Impacts:
Bypass Protection Mechanism Read Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: AI/ML, Web Based, Web Server
Likelihood of Exploit: High
View CWE Details
Application

Commonmark by Thephpleague

Product Information
Vendor Thephpleague
Product Commonmark
Version Range Affected
To 2.8.1 (exclusive)
cpe:2.3:a:thephpleague:commonmark:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://github.com/thephpleague/commonmark/security/advisor…
https://github.com/thephpleague/commonmark/security/advisories/GHSA-4v6x-c7xx-h…