CVE-2026-24936

Critical

Published: 03 February 2026

Published

03 February 2026

Modified

19 February 2026

KEV Added

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Patch

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CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0006 17.2th percentile

Risk Priority 20 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-24936 is a critical-severity Improper Input Validation (CWE-20) vulnerability in Asustor Data Master. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 17.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and IA-8 (Identification and Authentication (Non-organizational Users)).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match

prevent

Directly mandates validation of information inputs at CGI program interfaces, preventing arbitrary data writes due to improper input parameters validation.

IA-8 Identification and Authentication (Non-organizational Users) good match

prevent

Requires identification and authentication for non-organizational users, blocking unauthenticated remote exploitation of the vulnerable CGI program.

AC-3 Access Enforcement good match

prevent

Enforces approved access authorizations to system resources, preventing unauthorized file writes enabled by the input validation flaw.

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.

attack.mitre.org →

T1505.003 Web Shell Persistence

Adversaries may backdoor web servers with web shells to establish persistent access to systems.

attack.mitre.org →

Why these techniques?

Unauthenticated arbitrary file write in public-facing CGI directly enables T1190 (Exploit Public-Facing Application) for initial access and T1505.003 (Web Shell) via placement of executable server-side code leading to full compromise.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

When a specific function is enabled while joining a AD Domain from ADM, an improper input parameters validation vulnerability in a specific CGI program allowing an unauthenticated remote attacker to write arbitrary data to any file on the system. By…

exploiting this vulnerability, attackers can overwrite critical system files, leading to a complete system compromise. Affected products and versions include: from ADM 4.1.0 through ADM 4.3.3.ROF1 as well as from ADM 5.0.0 through ADM 5.1.1.RCI1.

Deeper analysisAI

CVE-2026-24936 is an improper input parameters validation vulnerability (CWE-20) in a specific CGI program within ASUSTOR Data Master (ADM). The issue arises when a specific function is enabled while joining an Active Directory (AD) Domain. It affects ADM versions from 4.1.0 through 4.3.3.ROF1, as well as from 5.0.0 through 5.1.1.RCI1. The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity with high impacts on confidentiality, integrity, and availability.

An unauthenticated remote attacker can exploit this vulnerability over the network with low complexity and no user interaction required. Successful exploitation allows the attacker to write arbitrary data to any file on the system, including overwriting critical system files, which can lead to complete system compromise.

For details on mitigation, patches, or workarounds, refer to the ASUSTOR security advisory at https://www.asustor.com/security/security_advisory_detail?id=51.