CVE-2026-54161

The record

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.

Affected packages

Related vulnerabilities

• CVE-2026-116651 Tanium addressed an unauthorized code execution vulnerability in Threat Response. CWE-78
• CVE-2026-116650 Tanium addressed an unauthorized code execution vulnerability in Threat Response. CWE-78
• CVE-2026-118865 An authenticated OS command injection vulnerability exists in the Offline Download… CWE-78
• CVE-2026-121621 A command injection vulnerability was found in Argo CD Image Updater, where a proxy URL… CWE-78
• CVE-2026-121548 Jarun nnn through 5.3 contains an OS command injection vulnerability in plugins/togglex… CWE-78
• CVE-2026-121429 AzuraCast through 0.23.8 contains a command injection vulnerability that allows station… CWE-78
• CVE-2026-119742 Nagios XI before 2026R2 contains an OS command injection vulnerability in the MIB upload… CWE-78
• CVE-2026-77691 ZohoCorp ManageEngine Key Manager Plus versions before 7151 allow authenticated users to… CWE-78