Jenkins 2.318 and earlier, LTS 2.303.2 and earlier allows any agent to read and write the contents of any build directory stored in Jenkins with very few restrictions.
{
"versions": [
{
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},
{
"last_affected": "2.303.2"
},
{
"introduced": "0"
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{
"last_affected": "2.318"
}
]
}