CVE-2026-55673

What it is

PowSyBl (Power System Blocks) is a framework to build power system oriented software. Prior to 7.2.2, UnixLocalCommandExecutor and WindowsLocalCommandExecutor concatenate command arguments and environment variables into strings interpreted through bash -c or cmd /c without sufficient escaping. Attacker-controlled values reaching UnixLocalCommandExecutor.execute, WindowsLocalCommandExecutor.execute, LocalComputationManager.execute, ParallelLoadFlowActionSimulator.run, ActionSimulatorTool.run, AmplModelRunner.run, or AmplModelRunner.runAsync can break out of the intended command and execute arbitrary shell commands as the JVM user. The affected itools paths include action-simulator with task-count, security-analysis with external, and dynamic-security-analysis. Downstream CLI tools, libraries, REST front ends, and multi-tenant grid-analysis services that forward less-trusted contingency identifiers or computation parameters into these APIs can expose the injection remotely. This issue is fixed in version 7.2.2.

At a glance

Exploitability

Can be exploited over the network with a low-privilege account. High risk of service disruption.

Exploit odds

0.6% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-08-28 20:18 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-09-09 21:09 UTC Last updatedMost recent change to the record

Details

Published

2026-08-28 20:18 UTC

Last modified

2026-09-09 21:09 UTC

Exploit probability

0.6% · EPSS, next 30 days

Weakness

CWE-78 · OS command injection

Record status

Deferred

Attack profile CVSS 4.0 · 7.1

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

Low

User interaction

None

Confidentiality

None

Integrity

Low

Availability

High