Talkd, when given corrupt DNS information, can be used to execute arbitrary commands with root privileges.

telnetd for netkit 0.17 and earlier, and possibly other versions, on Debian GNU/Linux allows remote attackers to cause a denial of service (free of an invalid pointer), a different vulnerability than CVE-2001-0554.

telnet-server: no bounds checks in nextitem() function allows to remotely execute arbitrary code

utility.c in telnetd in netkit telnet through 0.17 allows remote attackers to execute arbitrary code via short writes or urgent data, because of a buffer overflow involving the netclear and nextitem functions.

krb5-appl: NULL pointer dereference

telnetd in GNU Inetutils through 2.3, MIT krb5-appl through 1.0.3, and derivative works has a NULL pointer dereference via 0xff 0xf7 or 0xff 0xf8. In a typical installation, the telnetd application would crash but the telnet service would remain available through inetd. However, if the telnetd application has many crashes within a short time interval, the telnet service would become unavailable after inetd logs a "telnet/tcp server failing (looping), service terminated" error. NOTE: MIT krb5-appl is not supported upstream but is shipped by a few Linux distributions. The affected code was removed from the supported MIT Kerberos 5 (aka krb5) product many years ago, at version 1.8.

netkit-rsh: possible overwrite of arbitrary files by a malicious rsh server

An issue was discovered in rcp in NetKit through 0.17. For an rcp operation, the server chooses which files/directories are sent to the client. However, the rcp client only performs cursory validation of the object name returned. A malicious rsh server (or Man-in-The-Middle attacker) can overwrite arbitrary files in a directory on the rcp client machine. This is similar to CVE-2019-6111.

netkit-rsh: rcp access restriction bypass

In NetKit through 0.17, rcp.c in the rcp client allows remote rsh servers to bypass intended access restrictions via the filename of . or an empty filename. The impact is modifying the permissions of the target directory on the client side. This is similar to CVE-2018-20685.