CVE-2024-7399

What it actually does

This is a path traversal flaw in Samsung MagicINFO 9 Server versions before 21.1050 that permits a low-privileged, network-accessible attacker to escape an intended server-side directory during a file-write operation. Because the write occurs with system-level authority, a successful attacker can place or overwrite files outside the allowed path, potentially leading to configuration tampering, service disruption, web-shell placement, privilege escalation, persistence, or full compromise of the application host. The vulnerability is actively exploited in the wild, is listed in CISA KEV, and has a very high EPSS probability, indicating broad attacker interest and practical exploitability.

Why it matters to the business

Compromise of a MagicINFO server can disrupt digital signage operations, allow unauthorized changes to displayed content, expose stored media or credentials, and provide attackers with a foothold inside the network. Because exploitation is active in the wild and the EPSS score is high, internet- or partner-accessible instances should be treated as urgent remediation targets. Although it is not currently flagged by CISA as used in ransomware campaigns, arbitrary system-level file write vulnerabilities are commonly chained into malware deployment, persistence, and lateral movement.

How an attack unfolds

An attacker first obtains or abuses low-privileged access to a vulnerable Samsung MagicINFO 9 Server and identifies a file-write feature or API that accepts a pathname. The attacker submits a crafted path containing traversal sequences or encoded traversal sequences so the server resolves the destination outside the intended directory. The vulnerable server fails to constrain the final canonical path and writes attacker-controlled content using system authority. Depending on where the file is written, the attacker may overwrite configuration files, plant executable content in a web-served or startup location, modify application behavior, create persistence, or cause denial of service. In real-world exploitation, attackers are likely to follow up by validating file placement, attempting code execution through a reachable web path or service restart, harvesting credentials and configuration data, and removing obvious request traces.

How to fix it

Upgrade Samsung MagicINFO 9 Server to version 21.1050 or later. Prioritize externally reachable, partner-accessible, and high-trust internal instances. If package inventories also show Alpine Linux v3.14 Ruby components associated with this vulnerability record, ensure ruby is updated to 2.7.8-r0 or later; deduplicate repeated package findings but verify every image, container, and host using the affected Alpine package stream. If immediate upgrade is not possible, restrict MagicINFO access to trusted administrative networks, place the service behind VPN or strong access controls, disable or limit file-upload/write features where feasible, enforce least-privilege service accounts, prevent the application from writing to executable or startup directories, and monitor aggressively for traversal attempts and unexpected file creation.

How to confirm the fix worked

Confirm the deployed Samsung MagicINFO 9 Server version is 21.1050 or later through the product UI, package metadata, installation manifest, or vendor-supported version command. For Linux/container inventories that report the Alpine v3.14 Ruby package, confirm ruby is at 2.7.8-r0 or later using the system package manager or image scanner. Validate exposure by enumerating listening services and confirming MagicINFO management interfaces are not publicly reachable unless explicitly required and protected. After patching, perform a safe authenticated negative test against file-write functionality using benign traversal payloads and confirm the server rejects the request and does not create files outside the intended directory. Review filesystem permissions to ensure the MagicINFO process cannot write to operating-system, service startup, web executable, or application binary directories.

Typical attack path

1. Identify a Samsung MagicINFO 9 Server instance exposed to the network or reachable after initial access.
2. Authenticate with or compromise a low-privileged account, because exploitation requires privileges according to the CVSS vector.
3. Probe file-upload or file-write functionality for acceptance of relative path components.
4. Send a crafted pathname using traversal patterns such as ../, ..\, or URL-encoded equivalents to escape the intended directory.
5. Write a test file outside the restricted directory to confirm arbitrary file-write capability.
6. Write or overwrite a higher-impact file, such as application content, configuration, scheduled task material, service files, or a web-accessible script where the platform supports it.
7. Trigger execution or application reload if needed, then establish persistence, collect data, tamper with signage content, or use the server as a pivot point.
8. Delete test files, rename tools, and clear or reduce log evidence where permissions allow.

How to detect it

Investigate web, reverse proxy, WAF, application, authentication, EDR, and operating-system file auditing logs for suspicious file-write requests and path traversal attempts involving MagicINFO. Focus on requests containing ../, ..\, double-encoded traversal, absolute Windows or Linux paths, or attempts to write into web roots, configuration directories, temporary execution locations, service startup folders, or scheduled task locations. Correlate successful HTTP responses after traversal payloads with new or modified files created by the MagicINFO application process or service account. Look for unusual child processes spawned by the application service, especially shells, scripting runtimes, archive utilities, download tools, or command interpreters. Review MagicINFO media/content directories and application deployment paths for recently created files with executable extensions, unexpected JSP/ASP/HTML/script content, renamed binaries, or files whose timestamps do not match deployment activity. Because exploitation is active in the wild, perform retrospective searches back at least to the public disclosure date if logs permit, and broaden the window around any exposed instance or suspicious authentication activity.

• ../
• ..\\
• %2e%2e%2f
• %2e%2e%5c
• %252e%252e%252f
• %c0%ae%c0%ae%c0%af
• /etc/passwd
• /etc/shadow
• C:\\Windows\\System32
• C:/Windows/System32
• WEB-INF/web.xml
• .jsp
• .jspx
• .war
• cmd.exe
• powershell.exe
• /bin/sh
• /bin/bash
• curl
• wget
• certutil.exe
• /tmp/
• C:\\Windows\\Temp\\
• MagicINFO

What your security team should do

• Treat this as a high-priority remediation item because it is in CISA KEV, has active in-the-wild exploitation, and has a high EPSS score.
• Inventory all Samsung MagicINFO 9 Server deployments and confirm whether any are below version 21.1050.
• Patch or upgrade vulnerable MagicINFO servers before the KEV due date of 2026-05-08, and much sooner for internet-facing or high-value deployments.
• Temporarily restrict access to MagicINFO administrative and file-management functions to trusted networks and named administrators only.
• Hunt for prior exploitation before or immediately after patching, focusing on path traversal requests, unexpected file writes, new web-accessible files, and modified configuration files.
• Check whether the MagicINFO service runs with excessive privileges; reduce service account permissions so arbitrary writes cannot affect system or executable paths.
• Deploy SIEM detections for encoded and unencoded traversal sequences targeting MagicINFO endpoints and for suspicious file creation by the MagicINFO service account.
• Review backups and known-good baselines for MagicINFO application directories, media repositories, web roots, scheduled task locations, and configuration files.
• If compromise indicators are found, isolate the server, preserve logs and filesystem evidence, rotate credentials stored or used by MagicINFO, and rebuild from trusted media after patching.
• For container or Linux package findings, update Alpine v3.14 ruby packages to 2.7.8-r0 or later across base images and downstream deployments.