Vulnerability · Published Aug 19, 2026 · Assigned by GitHub_M

CVE-2026-64851Grav Shortcode Core Plugin: Stored XSS in shortcode-core attribute handlers

High 8.5

In plain English

A high-severity cross-site scripting in grav-plugin-shortcode-core from getgrav. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 40% of all known vulnerabilities).

Severity (CVSS 4.0)8.5High

Exploit odds (30 days)0.5%top 60.0% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

Grav Shortcode Core Plugin allows for the development shortcode plugins that utilize the common format utilized by WordPress and BBCode. Prior to 6.2.2, Grav Shortcode Core passes shortcode syntax through Security::detectXss() because it contains no literal less-than character, then ColorShortcode.php and related attribute handlers concatenate an attacker-controlled parameter into HTML without encoding. An account with admin.pages permission can close the generated attribute and add an event handler, creating stored cross-site scripting that executes for visitors or administrators who view the page. This issue is fixed in version 6.2.2.

Affected products (as reported)

Vendor	Product	Versions
getgrav	grav-plugin-shortcode-core	< 6.2.2

Weakness: CWE-79 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N

References

https://github.com/getgrav/grav/security/advisories/GHSA-q5fw-vpqc-fgph x_refsource_CONFIRM
https://github.com/getgrav/grav-plugin-shortcode-core/commit/2a55eac8a2cc7f6c2d4923ab2fa7991039620597 x_refsource_MISC
https://github.com/getgrav/grav-plugin-shortcode-core/releases/tag/6.2.2 x_refsource_MISC