In Eclipse Jetty versions 9.4.21.v20190926, 9.4.22.v20191022, and 9.4.23.v20191118, the generation of default unhandled Error response content (in text/html and text/json Content-Type) does not escape Exception messages in stacktraces included in error output.
{
"versions": [
{
"introduced": "0"
},
{
"last_affected": "9.4.21-20190926"
},
{
"introduced": "0"
},
{
"last_affected": "9.4.22-20191022"
},
{
"introduced": "0"
},
{
"last_affected": "9.4.23-20191118"
}
]
}