CVE-2025-4677: ABB WebPro SNMP Card Auth Bypass Flaw

CVE-2025-4677 Overview

CVE-2025-4677 is an Insufficient Session Expiration vulnerability affecting ABB WebPro SNMP Card PowerValue and ABB WebPro SNMP Card PowerValue UL devices. This vulnerability (CWE-613) allows attackers on an adjacent network to exploit improper session management controls, potentially leading to denial of service conditions affecting device availability.

The vulnerability stems from the failure to properly invalidate user sessions after a period of inactivity or upon explicit logout, allowing session tokens to remain valid indefinitely or for extended periods beyond their intended lifespan.

Critical Impact

Attackers on an adjacent network can exploit insufficient session expiration to cause high availability impact on affected ABB WebPro SNMP Card devices without requiring authentication.

Affected Products

• ABB WebPro SNMP Card PowerValue through version 1.1.8.K
• ABB WebPro SNMP Card PowerValue UL through version 1.1.8.K

Discovery Timeline

• 2026-01-07 - CVE CVE-2025-4677 published to NVD
• 2026-01-08 - Last updated in NVD database

Technical Details for CVE-2025-4677

Vulnerability Analysis

This vulnerability represents a session management flaw where user sessions are not properly expired after the expected timeout period or upon user logout. The adjacent network attack vector indicates that an attacker must have network adjacency to the vulnerable device, such as being on the same local network segment or VLAN as the ABB WebPro SNMP Card.

The vulnerability does not require any privileges or user interaction to exploit, making it particularly concerning for environments where network segmentation is weak. While the vulnerability does not directly impact confidentiality or integrity, it poses a significant threat to system availability, potentially disrupting critical power management and monitoring capabilities.

Root Cause

The root cause is classified as CWE-613 (Insufficient Session Expiration). This weakness occurs when a web application does not sufficiently verify that a session token is still valid or does not properly terminate sessions. In the context of ABB WebPro SNMP Card devices, sessions may persist beyond their intended lifetime, allowing stale or hijacked session tokens to be reused by attackers.

Common manifestations of this weakness include:

• Session tokens that remain valid after explicit logout
• Lack of server-side session timeout enforcement
• Improper cleanup of session data when sessions should be invalidated
• Session tokens with excessively long validity periods

Attack Vector

The attack vector requires adjacent network access, meaning the attacker must be positioned on the same network segment as the target device. This could include:

1. An attacker who has compromised another device on the same network segment
2. An insider with physical or logical access to the management network
3. An attacker who has gained access through a wireless network connected to the same VLAN

Once positioned, the attacker can exploit the insufficient session expiration to cause denial of service conditions. The attack does not require authentication, making any exposed device potentially vulnerable to exploitation.

The exploitation mechanism involves leveraging sessions that have not been properly invalidated. An attacker can capture or reuse session tokens that should have expired, potentially flooding the device with requests or manipulating session state to exhaust resources and cause service disruption.

Detection Methods for CVE-2025-4677

Indicators of Compromise

• Unusual session activity patterns on ABB WebPro SNMP Card management interfaces
• Multiple concurrent sessions from unexpected IP addresses within the adjacent network
• Session tokens being reused after expected expiration timeframes
• Abnormal authentication log entries showing session persistence anomalies

Detection Strategies

• Monitor network traffic to and from ABB WebPro SNMP Card devices for unusual session patterns
• Implement network-based anomaly detection for the management interface ports
• Review device logs for authentication and session management events
• Deploy network segmentation monitoring to detect unauthorized adjacent network access

Monitoring Recommendations

• Configure SIEM rules to alert on multiple failed or unusual session activities targeting SNMP card management interfaces
• Implement network traffic analysis for devices running firmware version 1.1.8.K and earlier
• Establish baseline session duration metrics and alert on significant deviations
• Monitor for denial of service symptoms such as unresponsive management interfaces

How to Mitigate CVE-2025-4677

Immediate Actions Required

• Review and restrict network access to ABB WebPro SNMP Card devices using network segmentation and access control lists
• Implement strict VLAN isolation to limit adjacent network exposure
• Monitor affected devices for signs of exploitation or service degradation
• Contact ABB support for updated firmware availability and apply patches when released

Patch Information

ABB has published technical documentation regarding this vulnerability. Organizations should review the ABB Technical Document for official guidance on remediation steps and firmware updates.

Ensure all affected WebPro SNMP Card PowerValue and WebPro SNMP Card PowerValue UL devices running firmware through version 1.1.8.K are identified and scheduled for patching as updates become available.

Workarounds

• Implement network segmentation to isolate ABB WebPro SNMP Card devices from untrusted network segments
• Deploy firewall rules to restrict management interface access to authorized administrative workstations only
• Enable logging and monitoring on network devices to detect unauthorized access attempts
• Consider implementing a jump server or bastion host for administrative access to critical infrastructure devices

Network isolation remains the most effective mitigation when firmware updates are not immediately available. Ensure that management interfaces are not accessible from general user networks or segments where compromise risk is elevated.