CVE-2026-54161 (GCVE-0-2026-54161)

Vulnerability from cvelistv5 – Published: 2026-11-03 19:57 – Updated: 2026-11-03 22:39
VLAI
Title
upsmon: remote OS command injection (RCE) via attacker-controlled ups.alarm in NOTIFYCMD execution
Summary
Network UPS Tools is a collection of programs which provide a common interface for monitoring and administering UPS, PDU and SCD hardware. From 2.8.3 to 2.8.5, upsmon in clients/upsmon.c inserts the server-supplied ups.alarm value into shell commands executed by notify(), async_notify(), and wall(). When a monitored device reports an ALARM state and an operator has configured NOTIFYCMD with EXEC in NOTIFYFLAG ALARM, shell metacharacters in the alarm text are evaluated on POSIX or Windows and can execute arbitrary operating-system commands as the upsmon account, which is commonly root. An attacker can control the value through a malicious or compromised upsd, a man-in-the-middle on a plaintext upsd to upsmon connection, or a compromised UPS device whose driver supplies the alarm upstream of upsd; TLS between upsd and upsmon does not mitigate the compromised-device path. This vulnerability is fixed in 2.8.6.
Severity
8.1 (High)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-03 22:36 UTC
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7868 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
networkupstools nut Affected: >= 2.8.3, <= 2.8.5
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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