A cross site scripting (XSS) vulnerability exists in Check_MK versions 1.4.0x prior to 1.4.0p6, allowing an unauthenticated remote attacker to inject arbitrary HTML or JavaScript via the _username parameter when attempting authentication to webapi.py, which is returned unencoded with content type text/html.
{
"versions": [
{
"introduced": "0"
},
{
"last_affected": "1.4.0"
},
{
"introduced": "0"
},
{
"last_affected": "1.4.0-p1"
},
{
"introduced": "0"
},
{
"last_affected": "1.4.0-p2"
},
{
"introduced": "0"
},
{
"last_affected": "1.4.0-p3"
},
{
"introduced": "0"
},
{
"last_affected": "1.4.0-p4"
},
{
"introduced": "0"
},
{
"last_affected": "1.4.0-p5"
}
]
}