snmp: Special characters not supported in options --v3-auth-prot-password and --v3-priv-prot-password

[michaje-gsc]

This issue respects the following points:

• This is a bug, not a question or a setup/configuration issue.
• This issue is not already reported on Github (I've searched it).
• I use the latest release of the Monitoring Plugins (https://github.com/Linuxfabrik/monitoring-plugins/releases).
• I agree to follow Monitoring Plugins's Code of Conduct.

Which variant of the Monitoring Plugins do you use?

• .rpm/.deb package from repo.linuxfabrik.ch
• Compiled for Linux from download.linuxfabrik.ch
• Compiled for Windows from download.linuxfabrik.ch
• Source Code from GitHub

Bug description

When using the following characters as part of values for --v3-auth-prot-password and/or --v3-priv-prot-password, inconsistent behaviour is observed:
#*$!&^

The following plugin output has been observed, together with a return code of 3 (Unknown):

# ./snmp --device lb-alteon-any.csv --hostname 10.9.8.7 --snmp-version 3 --timeout 2 --v3-auth-prot SHA --v3-auth-prot-password 'abc&def#ghi*jkl$mno' --v3-level authPriv --v3-priv-prot AES --v3-priv-prot-password 'pqr!stu^vwx&yz' --v3-username test
/bin/sh: line 1: yz: command not found
/bin/sh: line 1: def#ghi*jkl: command not found
Error: passphrase chosen is below the length requirements of the USM (min=8).
snmpget:  (The supplied password length is too short.)
Error generating a key (Ku) from the supplied authentication pass phrase.
#

NB: The behaviour is observed regardless the value and validity of other parameters, so this issue is very easy to reproduce.

Steps to reproduce - Plugin call

./snmp --device lb-alteon-any.csv --hostname 10.9.8.7 --snmp-version 3 --timeout 2 --v3-auth-prot SHA --v3-auth-prot-password 'abc&def#ghi*jkl$mno' --v3-level authPriv --v3-priv-prot AES --v3-priv-prot-password 'pqr!stu^vwx&yz' --v3-username test

Steps to reproduce - Data

/bin/sh: line 1: yz: command not found
/bin/sh: line 1: def#ghi*jkl: command not found
Error: passphrase chosen is below the length requirements of the USM (min=8).
snmpget:  (The supplied password length is too short.)
Error generating a key (Ku) from the supplied authentication pass phrase.

Environment

RHEL 9.5 5.14.0-503.40.1.el9_5.x86_64

Plugin Version

# ./snmp --version
snmp: v2025021501 by Linuxfabrik GmbH, Zurich/Switzerland
#
# file snmp
snmp: ELF 64-bit LSB pie executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=de2916dbb9553346a1b02b6d3785fc707ada8d10, for GNU/Linux 3.2.0, stripped
#

Python version

No response

List of Python modules

No response

Additional Information

No response