CVE-2026-23520

CriticalPublic PoCRCE

Published: 15 January 2026

Published

15 January 2026

Modified

05 February 2026

KEV Added

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Patch

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CVSS Score 9.0 CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H

EPSS Score 0.0003 9.7th percentile

Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-23520 is a critical-severity OS Command Injection (CWE-78) vulnerability in Arcane Arcane. Its CVSS base score is 9.0 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 9.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 AC-6 (Least Privilege) and CM-5 (Access Restrictions for Change).

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

Requires validation of untrusted lifecycle label inputs before passing them to /bin/sh -c, directly preventing command injection in the updater service.

AC-6 Least Privilege good match

prevent

Enforces least privilege to restrict project creation and lifecycle label setting via API to authorized users only, blocking low-privilege authenticated attackers.

CM-5 Access Restrictions for Change good match

prevent

Authorizes and restricts modifications to project configurations including executable lifecycle labels, preventing unauthorized injection during container updates.

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 →

T1059.004 Unix Shell Execution

Adversaries may abuse Unix shell commands and scripts for execution.

attack.mitre.org →

Why these techniques?

CVE describes unauthenticated command injection via API labels passed to /bin/sh -c, directly enabling exploitation of the management application (T1190) for Unix shell command execution (T1059.004) inside containers.

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

NVD Description

Arcane provides modern docker management. Prior to 1.13.0, Arcane has a command injection in the updater service. Arcane’s updater service supported lifecycle labels com.getarcaneapp.arcane.lifecycle.pre-update and com.getarcaneapp.arcane.lifecycle.post-update that allowed defining a command to run before or after a container update. The…

label value is passed directly to /bin/sh -c without sanitization or validation. Because any authenticated user (not limited to administrators) can create projects through the API, an attacker can create a project that specifies one of these lifecycle labels with a malicious command. When an administrator later triggers a container update (either manually or via scheduled update checks), Arcane reads the lifecycle label and executes its value as a shell command inside the container. This vulnerability is fixed in 1.13.0.

Deeper analysisAI

CVE-2026-23520 is a command injection vulnerability (CWE-78) in the updater service of Arcane, a modern Docker management tool, affecting versions prior to 1.13.0. The issue stems from the updater service's handling of lifecycle labels—specifically com.getarcaneapp.arcane.lifecycle.pre-update and com.getarcaneapp.arcane.lifecycle.post-update—which allow users to define commands to execute before or after a container update. These label values are passed directly to /bin/sh -c without any sanitization or validation, enabling arbitrary shell command execution. The vulnerability carries a CVSS v3.1 base score of 9.0 (AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H).

Any authenticated user, not limited to administrators, can exploit this vulnerability by creating a project through the Arcane API and specifying a malicious command in one of the lifecycle labels. Exploitation occurs when an administrator triggers a container update—either manually or via scheduled update checks—at which point Arcane reads the label and executes the command inside the container. This grants the attacker arbitrary code execution within the container context, potentially leading to high confidentiality, integrity, and availability impacts, including full container compromise.

The vulnerability is addressed in Arcane version 1.13.0, as detailed in the project's security advisory (GHSA-gjqq-6r35-w3r8), release notes, associated pull request #1468, and fixing commit 5a9c2f92e11f86f8997da8c672844468f930b7e4. Security practitioners should upgrade to 1.13.0 or later and review projects for malicious lifecycle labels, particularly in environments with low-privilege API access.