Multiple Siemens Simatic S7 programmable logic controller products contain multiple vulnerabilities that could allow an attacker to execute arbitrary code or cause a denial of service (DoS) condition on a targeted system.
The first vulnerability is due to insufficient security restrictions imposed on user sessions by the affected software. An unauthenticated, remote attacker could exploit this vulnerability by sniffing an existing session between a controller and the software. If successful, the attacker could conduct replay attacks on the system and possibly execute arbitrary code.
The second vulnerability is due to an unspecified error in the CPU of the affected controller. An unauthenticated, remote attacker could exploit this vulnerability by sending crafted requests to the system. The processing of the requests could cause the CPU to stop responding to user requests, resulting in a DoS condition.
Functional code that exploits this vulnerability is available as a part of the Metasploit framework.
Administrators may consider using IP-based access control lists (ACLs) to allow only trusted systems to access the affected systems.
Siemens SIMATIC S7-1200 and prior
CPU running on firmware version 02.00.02 is vulnerable.
Siemens has released a security advisory at the following link: SSA-625789
. Siemens has released patches at the following link: Simatic S7-1200
ICS-CERT has released a security advisory at the following link: ICS-ALERT-11-186-01