The mail message display page in SquirrelMail through 1.4.22 has XSS via a “<svg><a xlink:href=” attack.
www.openwall.com/lists/oss-security/2018/07/26/2
bugs.debian.org/905023
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CVXTYMZ35IC5KPNMAE6BWAQWURMX7KZO/
lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T5FP5O562A4FM5TCFNEW73SS6PZONSAC/
sourceforge.net/p/squirrelmail/bugs/2831/