In Horde Groupware, there has been an XSS vulnerability in two components via the Color field in a Create Task List action.

For Debian 9 stretch, this problem has been fixed in version 2.27.6+debian1-2+deb9u1.

We recommend that you upgrade your php-horde-core packages.

For the detailed security status of php-horde-core please refer to its security tracker page at: https://security-tracker.debian.org/tracker/php-horde-core

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: https://wiki.debian.org/LTS