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 "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.
References (4)
Core 4
Core References
Mailing List, Patch, Vendor Advisory
https://git.hadrons.org/cgit/debian/pkgs/inetutils.git/commit/?id=113da8021710d871c7dd72d2a4d5615d42d64289
Mailing List, Vendor Advisory
https://lists.gnu.org/archive/html/bug-inetutils/2022-08/msg00002.html
Exploit, Patch, Third Party Advisory
https://pierrekim.github.io/blog/2022-08-24-2-byte-dos-freebsd-netbsd-telnetd-netkit-telnetd-inetutils-telnetd-kerberos-telnetd.html
Mailing List, Third Party Advisory mailing-list
https://lists.debian.org/debian-lts-announce/2022/11/msg00033.html
Scores
CVSS v3
7.5
EPSS
0.0037
EPSS Percentile
58.9%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Details
CWE
CWE-476
Status
published
Products (4)
debian/debian_linux
10.0
gnu/inetutils
< 2.3
mit/kerberos_5
< 1.0.3
netkit-telnet_project/netkit-telnet
< 0.17
Published
Aug 30, 2022
Tracked Since
Feb 18, 2026