CVE-2022-26647 in SCALANCE X200-4P IRT
Summary
by MITRE • 07/12/2022
A vulnerability has been identified in SCALANCE X200-4P IRT (All versions), SCALANCE X200-4P IRT (All versions), SCALANCE X201-3P IRT (All versions), SCALANCE X201-3P IRT (All versions), SCALANCE X201-3P IRT PRO (All versions), SCALANCE X201-3P IRT PRO (All versions), SCALANCE X202-2IRT (All versions), SCALANCE X202-2IRT (All versions), SCALANCE X202-2P IRT (All versions), SCALANCE X202-2P IRT (All versions), SCALANCE X202-2P IRT PRO (All versions), SCALANCE X202-2P IRT PRO (All versions), SCALANCE X204-2 (All versions < V5.2.6), SCALANCE X204-2FM (All versions < V5.2.6), SCALANCE X204-2LD (All versions < V5.2.6), SCALANCE X204-2LD TS (All versions < V5.2.6), SCALANCE X204-2TS (All versions < V5.2.6), SCALANCE X204IRT (All versions), SCALANCE X204IRT (All versions), SCALANCE X204IRT PRO (All versions), SCALANCE X204IRT PRO (All versions), SCALANCE X206-1 (All versions < V5.2.6), SCALANCE X206-1LD (All versions < V5.2.6), SCALANCE X208 (All versions < V5.2.6), SCALANCE X208PRO (All versions < V5.2.6), SCALANCE X212-2 (All versions < V5.2.6), SCALANCE X212-2LD (All versions < V5.2.6), SCALANCE X216 (All versions < V5.2.6), SCALANCE X224 (All versions < V5.2.6), SCALANCE XF201-3P IRT (All versions), SCALANCE XF202-2P IRT (All versions), SCALANCE XF204 (All versions < V5.2.6), SCALANCE XF204-2 (All versions < V5.2.6), SCALANCE XF204-2BA IRT (All versions), SCALANCE XF204IRT (All versions), SCALANCE XF204IRT (All versions), SCALANCE XF206-1 (All versions < V5.2.6), SCALANCE XF208 (All versions < V5.2.6). The webserver of affected devices calculates session ids and nonces in an insecure manner. This could allow an unauthenticated remote attacker to brute-force session ids and hijack existing sessions.
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Analysis
by VulDB Data Team • 07/21/2022
This vulnerability affects a wide range of Siemens SCALANCE industrial network devices including various models from the X200, X201, X202, X204, X206, X208, X212, X216, X224, and XF series. The core issue lies in the insecure calculation of session identifiers and nonces within the web server component of these devices. This flaw represents a significant security weakness that directly impacts the authentication and session management mechanisms of the affected industrial control systems.
The technical flaw stems from predictable or insufficiently random session identifier generation, which creates opportunities for attackers to guess valid session tokens through brute force techniques. According to CWE-330, this vulnerability maps to the weakness of using insufficiently random values for security purposes, specifically in session management contexts. The insecure generation of cryptographic nonces and session identifiers fundamentally undermines the security model of the web interface, as these values should be cryptographically secure and unpredictable to prevent session hijacking attacks.
The operational impact of this vulnerability is severe for industrial environments where these devices operate. An unauthenticated remote attacker who can successfully brute-force session identifiers gains the ability to hijack existing user sessions without requiring valid credentials. This compromises the integrity of the device management interface and potentially allows full administrative control over the affected industrial network equipment. The attack surface extends beyond simple privilege escalation to include potential disruption of industrial processes, unauthorized configuration changes, and possible lateral movement within industrial networks. The vulnerability affects devices across multiple product lines and versions, indicating a systemic issue in the software implementation rather than isolated product-specific problems.
Mitigation strategies should include immediate deployment of firmware updates from Siemens addressing the session management implementation. Organizations should also implement network segmentation to limit access to these devices, disable unnecessary web interfaces where possible, and monitor network traffic for suspicious session hijacking attempts. The ATT&CK framework categorizes this vulnerability under T1110.003 - Brute Force: Password Guessing, with potential lateral movement through T1566 - Phishing and T1071.004 - Application Layer Protocol: DNS, as attackers may use these compromised sessions to establish further network access. Network administrators should also consider implementing additional authentication mechanisms and monitoring for anomalous session activity patterns that might indicate brute force attempts against the web interface.