CVE-2022-39028 Information

Description

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 elnet/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.

Reference

https://lists.gnu.org/archive/html/bug-inetutils/2022-08/msg00002.html https://git.hadrons.org/cgit/debian/pkgs/inetutils.git/commit/?id=113da8021710d871c7dd72d2a4d5615d42d64289 https://pierrekim.github.io/blog/2022-08-24-2-byte-dos-freebsd-netbsd-telnetd-netkit-telnetd-inetutils-telnetd-kerberos-telnetd.html