There is XSS in SilverStripe CMS before 3.4.4 and 3.5.x before 3.5.2. The attack vector is a page name. An example payload is a crafted JavaScript event handler within a malformed SVG element.
{
"versions": [
{
"introduced": "0"
},
{
"last_affected": "3.4.3"
},
{
"introduced": "0"
},
{
"last_affected": "3.5.0"
},
{
"introduced": "0"
},
{
"last_affected": "3.5.1"
}
]
}