Description

The My Calendar – Accessible Event Manager plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `template` attribute of the `[my_calendar_upcoming]` shortcode in all versions up to, and including, 3.7.3. This is due to the use of `stripcslashes()` on user-supplied shortcode attribute values in the `mc_draw_template()` function, which decodes C-style hex escape sequences (e.g., `\x3c` to `<`) at render time, bypassing WordPress's `wp_kses_post()` content sanitization that runs at save time. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Weaknesses 1

References 6

• plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/my-calendar/tags/3.7.2/my-calendar-shortcodes.php#L112
• plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/my-calendar/tags/3.7.2/my-calendar-templates.php#L83
• plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/my-calendar/trunk/my-calendar-shortcodes.php#L112
• plugins.trac.wordpress.org https://plugins.trac.wordpress.org/browser/my-calendar/trunk/my-calendar-templates.php#L83
• plugins.trac.wordpress.org https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&new=3464603%40my-calendar%2Ftrunk&old=3454989%40my-calendar%2Ftrunk&sfp_email=&sfph_mail=#file6
• wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/03d5c82e-f82f-4156-bb3e-e6eb365a6c36?source=cve

Remediation