CVE-2026-123039

CVE-2026-123039 is a local privilege escalation vulnerability affecting the DynamicCLI service (specifically the DynamicCLI IPC interface) in Check Point's Gaia operating system. The vulnerability stems from a missing authorization flaw where the DynamicCLI daemon runs as root and listens on a world-writable local socket (`/tmp/dynamic_socket`) without authenticating connecting processes. This allows any authenticated local user or lower-privileged process to execute arbitrary commands with root privileges by writing a single request to the socket. In late October and early November 2026, threat actors actively exploited this vulnerability in the wild alongside "PHP2Shell" remote code execution flaws. After gaining initial access to Check Point Security Gateways through the Mobile Access portal, attackers leveraged CVE-2026-123039 to escalate their privileges from a restricted service account to root. This elevated access allowed them to deploy persistent PHP webshells, install the TSGA backdoor, and in some cases, pivot to internal networks to deploy wiper malware. Check Point has since released emergency hotfixes to address the vulnerability.