CVE-2026-31151: Kaleris YMS Authentication Bypass Flaw

CVE-2026-31151 Overview

An authentication bypass vulnerability has been discovered in the login mechanism of Kaleris Yard Management System (YMS) version 7.2.2.1. This vulnerability allows attackers to bypass login verification and gain unauthorized access to the application's protected resources without valid credentials.

Critical Impact

Attackers can bypass authentication controls entirely, potentially gaining full access to yard management operations, sensitive logistics data, and administrative functions within the Kaleris YMS platform.

Affected Products

• Kaleris YMS v7.2.2.1

Discovery Timeline

• April 6, 2026 - CVE-2026-31151 published to NVD
• April 7, 2026 - Last updated in NVD database

Technical Details for CVE-2026-31151

Vulnerability Analysis

This vulnerability is classified as CWE-288 (Authentication Bypass Using an Alternate Path or Channel). The flaw resides in the login mechanism of Kaleris YMS, where improper validation allows attackers to circumvent the standard authentication process. Rather than exploiting a weakness in credential verification itself, this vulnerability enables attackers to access protected resources through an alternate path that does not properly enforce authentication requirements.

The network-accessible nature of this vulnerability means that attackers can exploit it remotely without requiring any prior authentication or user interaction. Successful exploitation grants unauthorized access to the application, compromising the confidentiality, integrity, and availability of the system and its data.

Root Cause

The root cause stems from insufficient authentication controls in the login mechanism. The application fails to properly validate authentication state when accessing protected resources, allowing requests to bypass the login verification process entirely. This represents a fundamental design flaw in how the application enforces access control boundaries between authenticated and unauthenticated sessions.

Attack Vector

The attack can be executed remotely over the network with low complexity. An attacker does not require any privileges or user interaction to exploit this vulnerability. By crafting specific requests that bypass the authentication checks, an attacker can directly access resources that should be restricted to authenticated users only.

Security researchers have published proof-of-concept details demonstrating this authentication bypass. For technical details on the exploitation method, refer to the GitHub CVE PoC Repository.

Detection Methods for CVE-2026-31151

Indicators of Compromise

• Unusual access to protected YMS resources without corresponding authentication log entries
• HTTP requests accessing application endpoints with missing or malformed session tokens
• Access patterns showing direct navigation to restricted pages bypassing the login workflow
• Anomalous user sessions with incomplete authentication records

Detection Strategies

• Monitor web application logs for requests to protected resources that lack valid session identifiers
• Implement anomaly detection for access patterns that skip the standard login flow
• Review access logs for requests to administrative or sensitive endpoints from unauthenticated sources
• Deploy web application firewall rules to detect authentication bypass attempts

Monitoring Recommendations

• Enable comprehensive logging for all authentication events and access attempts
• Configure alerts for access to sensitive resources without preceding successful login events
• Monitor for unusual traffic patterns targeting the Kaleris YMS login mechanism
• Implement session tracking to identify potential unauthorized access attempts

How to Mitigate CVE-2026-31151

Immediate Actions Required

• Restrict network access to Kaleris YMS instances to trusted networks only
• Implement additional authentication layers such as VPN or network segmentation
• Review access logs for signs of exploitation prior to remediation
• Contact Kaleris support for guidance on available security updates

Patch Information

Organizations running Kaleris YMS v7.2.2.1 should contact Kaleris directly to obtain information about security patches or updated versions that address this authentication bypass vulnerability. No vendor advisory has been published at this time.

Workarounds

• Deploy a web application firewall (WAF) to filter malicious requests targeting the login mechanism
• Restrict access to the YMS application to internal networks or VPN-only access
• Implement IP allowlisting to limit which addresses can reach the application
• Enable additional authentication controls at the network layer while awaiting a vendor patch

# Network-level access restriction example (firewall rule)
# Restrict Kaleris YMS access to trusted internal network only
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/8 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP