Grav before 2.0.14 Stored XSS via Invalid UTF-8 Byte
Grav before 2.0.14 contains a stored cross-site scripting vulnerability in the Security::detectXss() function (system/src/Grav/Common/Security.php). All XSS detection patterns use the PCRE /u (UTF-8) modifier, so a single invalid UTF-8 byte anywhere in page content causes preg_match() to return false for every pattern, silently bypassing the save-time XSS safety gate (Validation::checkSafety()). An authenticated attacker with page-edit permissions (without the security.xss_whitelist privilege) can store malicious JavaScript that executes in the browser of a visitor who views the affected page.
CVE-2026-75834
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-75834
grav
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"vendor": "getgrav",
"product": "grav",
"versions": [
{
"status": "affected",
"version": "0",
"lessThan": "2.0.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "2.0.14",
"versionType": "semver"
}
],
"packageURL": "pkg:composer/getgrav/grav",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-75834
Source reference:
/cveMetadata/cveId
Publisher severity
medium
Source reference: /containers/cna/metrics
- Event
- #12871 · Revision 1
- Added to Heist Feed
- Publisher date