Updated nethack packages fix security vulnerabilities:
NetHack 3.6.x before 3.6.4 is prone to a buffer overflow vulnerability when reading very long lines from configuration files. This affects systems that have NetHack installed suid/sgid, and shared systems that allow users to upload their own configuration files (CVE-2019-19905).
In NetHack before 3.6.5, unknown options starting with -de and -i can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to influence command line options (CVE-2020-5209).
In NetHack before 3.6.5, an invalid argument to the -w command line option can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to influence command line options (CVE-2020-5210).
In NetHack before 3.6.5, an invalid extended command in value for the AUTOCOMPLETE configuration file option can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to upload their own configuration files (CVE-2020-5211).
In NetHack before 3.6.5, an extremely long value for the MENUCOLOR configuration file option can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to upload their own configuration files (CVE-2020-5212).
In NetHack before 3.6.5, too long of a value for the SYMBOL configuration file option can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to upload their own configuration files (CVE-2020-5213).
In NetHack before 3.6.5, detecting an unknown configuration file option can cause a buffer overflow resulting in a crash or remote code execution/privilege escalation. This vulnerability affects systems that have NetHack installed suid/sgid and shared systems that allow users to upload their own configuration files (CVE-2020-5214).
In NetHack before 3.6.6, some out-of-bound values for the hilite_status option can be exploited (CVE-2020-5254).
The nethack package has been updated to version 3.6.6, fixing these issues and other bugs. See the upstream release notes for details.