In Puma (RubyGem) before 4.3.4 and 3.12.5, an attacker could smuggle an HTTP response, by using an invalid transfer-encoding header. The problem has been fixed in Puma 3.12.5 and Puma 4.3.4.
{
"unresolved_ranges": [
{
"extracted_events": [
{
"last_affected": "9.0"
}
],
"source": "CPE_FIELD",
"cpe": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*"
},
{
"extracted_events": [
{
"last_affected": "33"
}
],
"source": "CPE_FIELD",
"cpe": "cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*"
}
]
}