Malware
Plague
According to Nexttron Systems, this is an implant built as a malicious PAM (Pluggable Authentication Module), enabling attackers to silently bypass system authentication and gain persistent SSH access
Plague is a Linux malware family.
Background
Nexttron Systems describes this as an implant disguised as a rogue PAM (Pluggable Authentication Module), letting attackers quietly sidestep system authentication and maintain ongoing SSH access.
Source: Malpedia (Fraunhofer FKIE).