Emerson Appleton UPSMON-PRO

All CISA Advisories

Overview

The Emerson Appleton UPSMON-PRO vulnerability, identified as CVE-2024-3871, is a stack-based buffer overflow that could allow remote attackers to execute arbitrary code with SYSTEM privileges. This critical vulnerability, with a CVSS v4 score of 9.3, affects versions 2.6 and prior of the product, which is now End of Life and unsupported, necessitating immediate action from users.

Key Takeaways

  • Affected Systems: Affected products include Emerson Appleton UPSMON-PRO versions 2.6 and prior. The vulnerability could affect critical infrastructure sectors such as Critical Manufacturing, Healthcare, and Public Health worldwide.
  • Action Required: Users are recommended to replace the Appleton UPSMON-PRO product or apply the following mitigations: block UDP port 2601 at the firewall level for all installations, isolate UPS monitoring networks from general corporate networks, implement network-level packet filtering to reject oversized UDP packets to port 2601, and monitor for UPSMONProSer.
  • Timeline: Disclosed on November 20, 2025

Original Article Summary

View CSAF 1. EXECUTIVE SUMMARY CVSS v4 9.3 ATTENTION: Exploitable remotely/low attack complexity Vendor: Emerson Equipment: Appleton UPSMON-PRO Vulnerability: Stack-based Buffer Overflow 2. RISK EVALUATION Successful exploitation of this vulnerability could allow remote attackers to execute arbitrary code on affected installations of Appleton UPSMON-PRO. 3. TECHNICAL DETAILS 3.1 AFFECTED PRODUCTS The following Emerson products are affected: Appleton UPSMON-PRO: Versions 2.6 and prior 3.2 VULNERABILITY OVERVIEW 3.2.1 STACK-BASED BUFFER OVERFLOW CWE-121 A crafted UDP packet sent to the default UDP port 2601 can cause an overflow of the buffer stack, overwriting critical memory locations. This could allow unauthorized individuals to execute arbitrary code with SYSTEM privileges if the UPSMONProService service communication is not properly validated. CVE-2024-3871 has been assigned to this vulnerability. A CVSS v3.1 base score of 9.8 has been calculated; the CVSS vector string is (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H). A CVSS v4 score has also been calculated for CVE-2024-3871. A base score of 9.3 has been calculated; the CVSS vector string is (AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N). 3.3 BACKGROUND CRITICAL INFRASTRUCTURE SECTORS: Critical Manufacturing, Healthcare and Public Health COUNTRIES/AREAS DEPLOYED: Worldwide COMPANY HEADQUARTERS LOCATION: United States 3.4 RESEARCHER kimiya working with Trend Micro's Zero Day Initiative reported this vulnerability to CISA. 4. MITIGATIONS According to Emerson, Appleton UPSMON-PRO is End of Life and unsupported. Any users still using the product are recommended to replace the product or apply the following mitigations based on your company policies and Cybersecurity Operational recommendations. Recommended Actions if not replaced: Block UDP port 2601 at firewall level for all UPSMON-PRO installations Isolate UPS monitoring networks from general corporate networks Implement network-level packet filtering to reject oversized UDP packets to port 2601 Monitor for UPSMONProSer.exe service crashes as potential indicators of exploitation attempts Long-term Strategy Recommendation: Replace UPSMON-PRO with actively supported UPS monitoring solution Implement defense-in-depth strategies for critical power infrastructure monitoring CISA recommends users take defensive measures to minimize the risk of exploitation of this vulnerability, such as: Minimize network exposure for all control system devices and/or systems, ensuring they are not accessible from the internet. Locate control system networks and remote devices behind firewalls and isolating them from business networks. When remote access is required, use more secure methods, such as Virtual Private Networks (VPNs), recognizing VPNs may have vulnerabilities and should be updated to the most current version available. Also recognize VPN is only as secure as the connected devices. CISA reminds organizations to perform proper impact analysis and risk assessment prior to deploying defensive measures. CISA also provides a section for control systems security recommended practices on the ICS webpage on cisa.gov/ics. Several CISA products detailing cyber defense best practices are available for reading and download, including Improving Industrial Control Systems Cybersecurity with Defense-in-Depth Strategies. CISA encourages organizations to implement recommended cybersecurity strategies for proactive defense of ICS assets. Additional mitigation guidance and recommended practices are publicly available on the ICS webpage at cisa.gov/ics in the technical information paper, ICS-TIP-12-146-01B--Targeted Cyber Intrusion Detection and Mitigation Strategies. Organizations observing suspected malicious activity should follow established internal procedures and report findings to CISA for tracking and correlation against other incidents. No known public exploitation specifically targeting this vulnerability has been reported to CISA at this time. 5. UPDATE HISTORY November 20, 2025: Initial Publication

Impact

Affected products include Emerson Appleton UPSMON-PRO versions 2.6 and prior. The vulnerability could affect critical infrastructure sectors such as Critical Manufacturing, Healthcare, and Public Health worldwide.

Exploitation Status

No active exploitation has been reported at this time. However, organizations should still apply patches promptly as proof-of-concept code may exist.

Timeline

Disclosed on November 20, 2025

Remediation

Users are recommended to replace the Appleton UPSMON-PRO product or apply the following mitigations: block UDP port 2601 at the firewall level for all installations, isolate UPS monitoring networks from general corporate networks, implement network-level packet filtering to reject oversized UDP packets to port 2601, and monitor for UPSMONProSer.exe service crashes. Long-term strategies include replacing UPSMON-PRO with an actively supported UPS monitoring solution and implementing defense-in-depth strategies for critical power infrastructure monitoring.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to CVE, Vulnerability, Update, and 2 more.

Related Coverage

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 84

Security Affairs

The latest Security Affairs Malware newsletter covers several significant malware threats that have emerged recently. Notably, a group identified as Stan Ghouls is targeting users in Russia and Uzbekistan using the NetSupport Remote Access Trojan (RAT), which allows attackers to control infected systems remotely. Another concerning development is the discovery of ZeroDayRAT, a new spyware designed to infiltrate both Android and iOS devices. Additionally, researchers have uncovered a Linux botnet named SSHStalker, which utilizes old-school IRC methods to compromise new victims. These activities demonstrate the evolving tactics of cybercriminals and emphasize the need for users and organizations to remain vigilant against these persistent threats.

Feb 15, 2026

Week in review: Exploited newly patched BeyondTrust RCE, United Airlines CISO on building resilience

Help Net Security

Last week, a newly patched vulnerability in BeyondTrust's Remote Code Execution (RCE) software was exploited in the wild. This vulnerability poses significant risks as it allows attackers to execute commands on affected systems without authorization. BeyondTrust has issued patches to address this issue, but organizations using the affected software need to act quickly to apply these updates to prevent potential breaches. Additionally, in an interview, Deneen DeFiore, the Chief Information Security Officer at United Airlines, discussed the importance of resilience in cybersecurity. She emphasized that while prevention is crucial, organizations must also prepare for disruptions and manage risks associated with their interconnected vendor and partner ecosystems. This dual focus on resilience and safety is essential for maintaining operational integrity in today's complex digital landscape.

Feb 15, 2026

287 Chrome Extensions Caught Harvesting Browsing Data from 37M Users

Hackread – Cybersecurity News, Data Breaches, AI and More

A recent investigation by Q Continuum has uncovered that 287 Chrome extensions are leaking private browsing data from approximately 37.4 million users to companies like Similarweb and Alibaba. These extensions, often perceived as harmless tools, have been found to convert users' browsing histories into marketable products. The data breach raises significant privacy concerns, particularly for users who may not be aware that their online activities are being monitored and sold. This incident highlights the need for users to be vigilant about the extensions they install and the permissions they grant. As these extensions may not seem malicious at first glance, it serves as a reminder of the potential risks associated with browser add-ons.

Feb 14, 2026

Fintech firm Figure disclosed data breach after employee phishing attack

Security Affairs

Fintech company Figure has confirmed a data breach resulting from a phishing attack that targeted one of its employees. The attackers used social engineering tactics to deceive the employee and gain access to a limited number of files. A spokesperson for Figure stated that while the breach is concerning, the extent of the data compromised is not extensive. This incident raises alarms about the effectiveness of employee training and awareness regarding phishing tactics, which continue to be a significant vulnerability for many organizations. Users and stakeholders of Figure should remain vigilant and monitor for any unusual activity related to their accounts.

Feb 14, 2026

One threat actor responsible for 83% of recent Ivanti RCE attacks

BleepingComputer

Recent threat intelligence reports indicate that a single threat actor is behind the majority of attacks exploiting two critical vulnerabilities in Ivanti Endpoint Manager Mobile (EPMM), identified as CVE-2026-21962 and CVE-2026-24061. These vulnerabilities allow for remote code execution, posing significant risks to organizations using this mobile management solution. The findings suggest that companies using Ivanti's software need to be vigilant, as the attacks are actively occurring. The focus on a single actor highlights the need for targeted defenses against this specific threat. Organizations are encouraged to monitor for unusual activity and apply any available patches to mitigate potential exploitation.

Feb 14, 2026

Snail mail letters target Trezor and Ledger users in crypto-theft attacks

BleepingComputer

Attackers are targeting users of cryptocurrency hardware wallets Trezor and Ledger by sending fake physical letters that appear to be from these companies. These letters aim to deceive users into revealing their recovery phrases, which can be used to steal their cryptocurrencies. This tactic exploits the trust users have in these well-known wallet providers and could lead to significant financial losses for those who fall for the scam. It’s crucial for users to be cautious and verify any communications they receive, especially when it comes to sensitive information like recovery phrases. The rise of such scams underscores the need for increased awareness and education around cryptocurrency security.

Feb 14, 2026