Silex SD-330AC/AMC Manager Vulnerability Advisory: Stack/Heap Overflow, Auth Bypass

Silex SD-330AC Multiple Vulnerabilities Summary Vulnerability Overview Multiple security vulnerabilities have been discovered in the Silex SD-330AC product. These vulnerabilities cannot be directly exploited from external networks (e.g., the Internet), but if an attacker can communicate with the affected product on the same local network, they may exploit these vulnerabilities to cause memory corruption, service disruption, or unauthorized configuration changes. No exploitation or damage reports have been identified so far. Impact Scope Affected Products: SD-330AC Version 1.42 and earlier AMC Manager Version 5.0.2 and earlier Detailed Vulnerability List 1. Web Configuration Interface Related Vulnerabilities CVE-2026-32955 (CVSS 8.8): Stack overflow in authenticated login redirect URL. May lead to memory corruption. Mitigation: Disable HTTP/HTTPS services. CVE-2026-32956 (CVSS 9.8): Heap overflow in unauthenticated login redirect URL. May lead to memory corruption. Mitigation: Disable HTTP/HTTPS services. CVE-2026-32957 (CVSS 5.3): Improper restrictions on file upload function. Allows uploading arbitrary files (but they will not be executed, no actual damage). Mitigation: Disable HTTP/HTTPS services. CVE-2026-32963 (CVSS 8.1): Reflected cross-site scripting (XSS) on system status page. Allows injection of malicious JavaScript. Mitigation: Disable HTTP/HTTPS services. 2. Firmware Update Related Vulnerabilities CVE-2026-32958 (CVSS 6.5): Hardcoded firmware signature key. Allows attackers to use forged firmware signature keys. Mitigation: Set a password for the web configuration interface. 3. SNMP Agent Related Vulnerabilities CVE-2015-5621 (CVSS 7.5): Denial of Service (DoS) vulnerability in net-snmp. Allows attackers to abnormally terminate the SNMP agent. Mitigation: Disable SNMP service. 4. AMC Manager Communication Related Vulnerabilities CVE-2026-32959 (CVSS 5.8): Encryption uses constant keystream. Allows man-in-the-middle attacks to obtain configuration data. Mitigation: None. CVE-2026-32960 (CVSS 6.5): Authentication bypass due to credential reuse. Allows attackers to reuse authenticated administrator credentials to gain privileges. Mitigation: None. CVE-2026-32961 (CVSS 5.3): Heap overflow due to insufficient data length validation. May lead to DoS or remote code execution. Mitigation: None. CVE-2026-32965 (CVSS 7.5): Product password can be set without administrator password. Allows attackers to set a password to gain administrator privileges. Mitigation: Set an administrator password for the web configuration interface. 5. Serial Device Server Settings Communication Related Vulnerabilities CVE-2026-32962 (CVSS 5.3): Product settings can be modified without authentication. Allows attackers to tamper with configurations. Mitigation: None. CVE-2026-24487 (CVSS 5.3): Product can be rebooted without authentication. Results in denial of service (DoS). Mitigation: None. CVE-2026-32964 (CVSS 6.5): Injection vulnerability in configuration processing. Allows unauthenticated attackers to insert arbitrary entries. Mitigation: None. Remediation Silex has provided firmware updates that include remediation measures. SD-330AC Firmware Version: 1.50 and later AMC Manager Version: 5.1.0 and later Restrictions and Changes After Applying Fixes: 1. Firmware Downgrade Restriction: Once new firmware is installed, downgrading to older versions is not possible. 2. Mandatory Configuration Step: Administrator password must be set before first use; otherwise, some features will be unavailable. 3. AMC Manager Compatibility: AMC Manager versions 5.0.2 and earlier are no longer compatible; use version 5.1.0 or later. 4. Serial Device Server Settings Tool:** Only available under factory default configuration. After completing initial setup, administrator password must be set first.

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Silex SD-330AC/AMC Manager Vulnerability Advisory: Stack/Heap Overflow, Auth Bypass