TI-2026-53080 Aliases CVE-2026-75834 GHSA-q2j8-x8hf-63ch

Grav before 2.0.14 Stored XSS via Invalid UTF-8 Byte

LOW 23CWE-79Published 2026-08-18 · Updated 2026-10-08

Key facts

Attack vector: Network
Privileges required: Low
User interaction: Passive
Attack complexity: Low
Attack requirements: None
Impact type: Cross-site scripting
Confidentiality · integrity · availability: None · None · None
Fix status: Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-79.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00255 17th percentileScored 2026-11-07

Fix Fixed grav (getgrav): 2.0.14getgrav/grav (Packagist): 2.0.14

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
getgrav	grav	before 2.0.14	2.0.14	Patch available	CNA
—	getgrav/grav (Packagist)	before 2.0.14	2.0.14	Patch available	GHSA-q2j8-x8hf-63ch

grav Vendorgetgrav Affected before 2.0.14 Fixed in 2.0.14 Patch available CNA
getgrav/grav (Packagist) Vendor— Affected before 2.0.14 Fixed in 2.0.14 Patch available GHSA-q2j8-x8hf-63ch

Remediation

Fix · CNA grav (getgrav) Fixed in 2.0.14
Fix · GHSA-q2j8-x8hf-63ch getgrav/grav (Packagist) Fixed in 2.0.14 Advisory →

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-08-18
getgrav grav 2.0.14
2 records Highest priority Priority HIGH 1 HIGH, 1 LOW
Other records, highest priority first
- TI-2026-53083 Grav before 2.0.14 Privilege Escalation via Group Access FieldPriority HIGH 75
Show all 2 records →

Timeline

2026-10-02 Threatist record created from CVE-2026-75834
2026-10-03 Alias added: GHSA-q2j8-x8hf-63ch

References

Advisory 2

Other 1

https://github.com/getgrav/grav

TI-2026-30893 Grav: Privilege Escalation via Missing Server-Side Validation of groups/access CVSS 3.1CRITICAL 9.4
TI-2025-28971 Cross Site Scripting vulnerability in grav v.1.7.48 and before allows an attacker to… CVSS 3.1CRITICAL 9.8
TI-2021-04523 Unauthenticated Arbitrary YAML Write/Update leads to Code Execution CVSS 3.1CRITICAL 9.8
TI-2026-50940 Grav CMS before 2.0.16 Origin Validation Bypass via Referer CVSS 4.0CRITICAL 9.3
TI-2026-46446 Grav before 2.0.7 Remote Code Execution via Blueprint dynamicData CVSS 4.0CRITICAL 9.3
TI-2021-22428 GravCMS 1.10.7 - Arbitrary YAML Write/Update (Unauthenticated) (2) CVSS 4.0CRITICAL 9.3

See all 228 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences