CVE-2026-64851
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.
What this means for your business
- FIRST's prediction model gives it a 0.5% chance of attack attempts being seen in the next 30 days, ranking above 37% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- Not yet scored
- CVSS v4
- 8.5
- Weakness
- CWE-79
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-08-19
- Last modified
- 2026-09-09
- Sources
- NVD
References
- https://github.com/getgrav/grav-plugin-shortcode-core/commit/2a55eac8a2cc7f6c2d4923ab2fa7991039620597
- https://github.com/getgrav/grav-plugin-shortcode-core/releases/tag/6.2.2
- https://github.com/getgrav/grav/security/advisories/GHSA-q5fw-vpqc-fgph
- https://github.com/getgrav/grav/security/advisories/GHSA-q5fw-vpqc-fgph