A user with read-only privileges is able to craft an aggregation pipeline using the $linearFill window function operator with a specific sortBy expression type to cause the mongod process to terminate abnormally, resulting in denial of service. The issue stems from insufficient validation of sort specifications during execution.
{
"binaries": [
{
"binary_name": "mongodb",
"binary_version": "1:3.6.3-0ubuntu1.4+esm2"
},
{
"binary_name": "mongodb-clients",
"binary_version": "1:3.6.3-0ubuntu1.4+esm2"
},
{
"binary_name": "mongodb-server",
"binary_version": "1:3.6.3-0ubuntu1.4+esm2"
},
{
"binary_name": "mongodb-server-core",
"binary_version": "1:3.6.3-0ubuntu1.4+esm2"
}
]
}
{
"binaries": [
{
"binary_name": "mongodb",
"binary_version": "1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1"
},
{
"binary_name": "mongodb-clients",
"binary_version": "1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1"
},
{
"binary_name": "mongodb-server",
"binary_version": "1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1"
},
{
"binary_name": "mongodb-server-core",
"binary_version": "1:3.6.9+really3.6.8+90~g8e540c0b6d-0ubuntu5.3+esm1"
}
]
}