CVE-2021-20599

Name of the Vulnerable Software and Affected Versions MELSEC iQ-R series Safety CPU R08/16/32/120SFCPU versions prior to 26 MELSEC iQ-R series SIL2 Process CPU R08/16/32/120PSFCPU versions prior to 11

Description The issue is related to the transmission of credentials in an unencrypted form, allowing a remote attacker to gain unauthorized access to protected information. This can enable an attacker to log in to a target CPU module by obtaining credentials other than a password.

Recommendations For MELSEC iQ-R series Safety CPU R08/16/32/120SFCPU versions prior to 26, update the firmware to version 27 or later. For MELSEC iQ-R series SIL2 Process CPU R08/16/32/120PSFCPU versions prior to 11, update the firmware to version 12 or later. As a temporary workaround, consider restricting access to the CPU modules to minimize the risk of exploitation.