KornShell is a Unix shell developed by AT&T Bell Laboratories, which is backward-compatible with the Bourne shell and includes many features of the C shell. The most recent version is KSH-93. KornShell complies with the POSIX.2 standard . Security Fix: * ksh: certain environment variables interpreted as arithmetic expressions on startup, leading to code injection For more details about the security issue, including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page listed in the References section.