HomeCVE Intelligence › CVE-2026-42612
CVSS 8.5 HIGH Vulnerability

CVE-2026-42612: Grav Vulnerable to Publisher-Level Stored XSS via Unquoted Event Attributes

Summary A stored Cross-Site Scripting (XSS) vulnerability in getgrav/grav allows publisher-level accounts to execute arbitrary JavaScript. The issue arises from a blacklist bypass in the detectXss() function when handli…

8.5CVSS Score
HIGHSeverity
NOCISA KEV
VulnerabilityImpact Type

📋 Vulnerability Details

CVE IDCVE-2026-42612
Vendorcomposer
Affected Productgetgrav/grav
Vulnerability TypeVulnerability
CVSS Score8.5 (HIGH)
Actively Exploited❌ No known exploitation
Patch StatusSee Vendor Advisory →
Reported ByCYBERDUDEBIVASH SENTINEL APEX Intelligence (via github_advisories)

🔬 Technical Analysis

#

Summary

A stored Cross-Site Scripting (XSS) vulnerability in getgrav/grav allows publisher-level accounts to execute arbitrary JavaScript. The issue arises from a blacklist bypass in the detectXss() function when handling unquoted HTML event attributes.

Details

The detectXss() function relies on a blacklist pattern to filter malicious attributes. The specific regex pattern used to match on* events is flawed: ``php 'on_events' => '#( ]+[a-z\x00-\x20\"\'\/])(on[a-z]+|xmlns)\s*=[\s|\'\"].*[\s|\'\"]>#iUu' ` This pattern fails to properly identify on*` event handlers that are constructed without quotation marks. This allows an attacker to completely bypass the filter. *Note: It is highly recommended to replace this blacklist approach with a robust, established HTML sanitizat

📚 Advisory References

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