Remote Yes

Type Arbitrary command execution

Description

Incomplete blacklist vulnerability in nrpe.c in Nagios Remote Plugin Executor (NRPE) 2.15 and earlier allows remote attackers to execute arbitrary commands via a newline character in the -a option to libexec/check_nrpe.

AVG-587 nrpe 3.2.1-2 3.2.1-3 High Fixed FS#57120

18 Jan 2018 ASA-201801-14 AVG-587 nrpe High arbitrary command execution

http://seclists.org/fulldisclosure/2014/Apr/240
http://seclists.org/oss-sec/2014/q2/154
https://github.com/NagiosEnterprises/nrpe/commit/eaaebb3c2925f9aee74319b61264ee535784b859

This issue can only occur when nrpc is compiled with --enable-command-args and the administrator enables the "dont_blame_nrpe" option in nrpe.conf despite the "HIGH security risk" warning within the comments.

Test Exploit:
./check_nrpe -n -H 127.0.0.1  -c check_users -a "`echo -e "\x0a touch /tmp/vulntest "` #" 4