Cyber Posture

CVE-2026-21389

High

Published: 27 February 2026

Published
27 February 2026
Modified
27 February 2026
KEV Added
Patch
CVSS Score 8.0 CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.0028 51.6th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Description

An OS command injection vulnerability exists in XWEB Pro version 1.12.1 and prior, enabling an authenticated attacker to achieve remote code execution on the system by injecting malicious input into the request body sent to the contacts import route.

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly prevents OS command injection by enforcing input validation and sanitization mechanisms at entry points like the contacts import route request body.

prevent

Mitigates the specific vulnerability through timely flaw remediation, such as applying vendor-provided software updates for XWEB Pro.

prevent

Complements input validation by restricting the types and characteristics of information accepted into the system, reducing opportunities for malicious command injection.

Security SummaryAI

CVE-2026-21389 is an OS command injection vulnerability (CWE-78) in XWEB Pro version 1.12.1 and prior. Published on 2026-02-27, it affects the contacts import route, where an attacker can inject malicious input into the request body to achieve remote code execution on the system. The vulnerability carries a CVSS v3.1 base score of 8.0 (AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H).

An authenticated attacker with high privileges (PR:H) can exploit this vulnerability remotely over the network (AV:N). Exploitation requires high attack complexity (AC:H) but no user interaction (UI:N), enabling a change in scope (S:C) with high impacts on confidentiality, integrity, and availability (C:H/I:H/A:H). Successful attacks result in full remote code execution on the affected system.

CISA's ICS Advisory ICSA-26-057-10 addresses this vulnerability, with details available at https://www.cisa.gov/news-events/ics-advisories/icsa-26-057-10 and in CSAF JSON format at https://github.com/cisagov/CSAF/blob/develop/csaf_files/OT/white/2026/icsa-26-057-10.json. Copeland provides system software updates for mitigation at https://webapps.copeland.com/Dixell/Pages/SystemSoftwareUpdate.

Details

CWE(s)

Affected Products

copeland
xweb 300d pro firmware
≤ 1.12.1
copeland
xweb 500d pro firmware
≤ 1.12.1
copeland
xweb 500b pro firmware
≤ 1.12.1

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
Why these techniques?

OS command injection vulnerability in a remotely accessible web application (contacts import route) directly enables exploitation of public-facing applications (T1190) and facilitates arbitrary OS command execution (T1059).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

References