Executive Summary
CVE-2026-2402 is a cluster of weaknesses in Schneider Electric PowerChute Serial Shutdown versions 1.4 and earlier that allow an attacker to overwrite critical files, forge or truncate log data, reset user credentials, and force denial of service against the shutdown management service. The physical criticality is that this software governs orderly shutdown of servers, HMIs, engineering workstations, and controllers when UPS power fails, so tampering with it converts a clean power-loss shutdown into an uncontrolled crash.
Technical Exposure Breakdown
PowerChute Serial Shutdown communicates with an APC or Schneider UPS over a serial link and executes host shutdown sequences when battery runtime crosses configured thresholds. The vulnerable component is the management service and its associated web interface, running with the privileges required to initiate operating system shutdown commands and to write configuration and log files.
The published CVSS score of 5.3 understates the operational risk because the base metric assumes an IT server context. The reported effects break into several distinct primitives. File overwrite means an attacker who reaches the service can alter shutdown scripts and configuration, changing which hosts shut down and in what order. Log forgery and truncation destroy the forensic record of when shutdown was triggered and by whom. Credential reset gives an attacker administrative control of the shutdown policy. Denial of service against the service means the software will not initiate shutdown at all when battery power actually runs out.
The precondition for exploitation is network or local access to the management interface. In many OT deployments PowerChute is installed on the same engineering workstation or supervisory host it protects, which means the attack surface sits inside the control network rather than in a segmented DMZ. There is no indication this is remotely exploitable across the internet without exposure of the management port, and the vulnerability is not flagged in the known exploited vulnerability catalog.
OT Impact and Compliance Risk
The failure mode that matters is not data theft. It is the loss of guaranteed graceful shutdown. If an attacker corrupts shutdown scripts or crashes the service, a UPS transfer to battery followed by battery exhaustion produces a hard power cut to controllers and supervisory hosts. Uncontrolled loss of power to a PLC or SCADA server risks configuration corruption, loss of the last-known process state, and extended restart times during which the operator is flying blind.
For IEC 62443 the relevant zones are system integrity and use control, specifically FR 1 and FR 3. Credential reset and unauthorized access defeat identification and authentication controls. Log truncation defeats the audit requirements under FR 6. For NERC CIP registered entities, PowerChute hosts frequently qualify as BES Cyber Assets or associated EACMS, so CIP-007 patch management and CIP-010 configuration monitoring apply directly, and the log tampering primitive undermines CIP-007 R4 security event monitoring. Water utilities operating under AWIA 2018 risk assessments should treat the shutdown host as a supporting asset whose failure degrades recovery time.
Compensating Controls
Do not treat active scanning of these hosts as a substitute for inventory. Aggressive probing of serial-attached UPS management stacks can hang the service and, in some cases, trigger the very shutdown behavior you are trying to protect. Confirm asset presence through configuration review and passive monitoring.
- Isolate the PowerChute management port. Bind the web interface to localhost only where the deployment supports it, and place any remote management behind a jump host with multifactor authentication.
- Enforce host firewall rules that permit management connections only from named engineering workstations. This is a virtual patch that shrinks the reachable attack surface without touching the vulnerable binary.
- Ship PowerChute logs off the host to a write-once collector in near real time so that on-host truncation or forgery does not erase the record.
- Deploy a Suricata rule concept that alerts on HTTP requests to the management interface from any source outside the approved workstation set, and on anomalous POST activity to configuration and credential endpoints.
- Validate shutdown scripts against a known-good hash on a schedule so that unauthorized file overwrite is detected before the next power event.
BreachSpider Intel tracks CVE-2026-2402 and related shutdown-management exposures across 25,000+ ICS CVEs, and BreachSpider monitoring can flag reachability changes to PowerChute hosts in your environment.