Plugin(centreon::common::cisco::standard::snmp) - Mode(vpc): peer MAC (cVpcSystemOperMacAddress) not normalized, may output non-UTF8 bytes

[DanielVdWP]

Quick description

The Cisco vPC SNMP mode prints cVpcSystemOperMacAddress (OctetString) raw in the output without normalization/sanitization. When the value is returned as non-UTF8/binary bytes (e.g., hex/octet dump), it can produce garbled characters and break monitoring UIs/pipelines (e.g., Icinga) that expect UTF-8 clean plugin output.

How to reproduce

• Environment:

  uname -a
  cat /etc/redhat-release /etc/debian_version

  Output:

  # uname -a
  Linux REDACTED 4.18.0-553.97.1.el8_10.x86_64 #1 SMP Tue Jan 20 00:58:00 EST 2026 x86_64 x86_64 x86_64 GNU/Linux
  # cat /etc/redhat-release
  Red Hat Enterprise Linux release 8.10 (Ootpa)

• Version of the plugin:

  • Repository: centreon/centreon-plugins
  • Branch: develop
  • File: src/centreon/common/cisco/standard/snmp/mode/vpc.pm
  • Commit/date: TODO (paste commit hash or last commit date)

• Information about the monitored resource:

  • Device: TODO (exact model, e.g., Nexus 9k/7k)
  • OS: TODO (NX-OS version)
  • vPC domain id: TODO (if known)

• Command line:

  centreon_plugins.pl \
    --plugin=centreon::common::cisco::standard::snmp::plugin \
    --mode=vpc \
    --hostname=<IP> \
    --snmp-version=2c \
    --community=<COMMUNITY>

  SNMP evidence (OctetString rendered as bytes):

  snmpget -v2c -c <COMMUNITY> -On -OQevx <IP> 1.3.6.1.4.1.9.9.807.1.2.1.1.5.<domain_id>

  Example output:

  "00 23 04 EE BE 50 "
  

Expected result

Plugin output should be UTF-8 safe and display the vPC peer MAC in a normalized format (e.g., 00:23:04:ee:be:50), or at least sanitize/escape non-printable bytes so the output is safe for monitoring UIs and storage backends.

Actual result

The plugin prints the MAC address raw (without normalization/sanitization). With some SNMP stacks/devices returning cVpcSystemOperMacAddress as an octet/hex dump (binary bytes), the plugin output contains non-printable/non-UTF8 characters or “strange” rendering, causing garbled output and issues in systems expecting clean UTF-8 (observed with Icinga).

Code reference

• OID used: cVpcSystemOperMacAddress .1.3.6.1.4.1.9.9.807.1.2.1.1.5
• In vpc.pm, the value is mapped to macaddress and printed directly in the peer prefix output (no formatting step), e.g.:
  • mapping: macaddress => { oid => '.1.3.6.1.4.1.9.9.807.1.2.1.1.5' }
  • output prefix uses peer '<macaddress>' without normalization

[rchauvel]

Thanks for this report, let us discuss a fix