An issue was discovered in includes/CommentFormatter/CommentParser.php in MediaWiki before 1.39.7, 1.40.x before 1.40.3, and 1.41.x before 1.41.1. XSS can occur because of mishandling of the 0x1b character, as demonstrated by Special:RecentChanges#%1b0000000.
{
"versions": [
{
"introduced": "0"
},
{
"fixed": "1.39.7"
},
{
"introduced": "1.40.0"
},
{
"fixed": "1.40.3"
},
{
"introduced": "1.41.0"
},
{
"fixed": "1.41.1"
}
]
}