CVE-2026-75834 (GCVE-0-2026-75834)
Vulnerability from cvelistv5
Published
2026-08-18 11:19
Modified
2026-08-18 13:36
Severity ?
5.1 (Medium) - CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
5.4 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
5.4 (Medium) - CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
VLAI Severity ?
EPSS score ?
CWE
- CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Summary
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.
References
| URL | Tags | |
|---|---|---|
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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