CVE-1999-1513 is a high-severity vulnerability affecting the Management Information Base (MIB) of the 3Com SuperStack II hub running software version 2.10. The MIB contains an object identifier (.1.3.6.1.4.1.43.10.4.2) that is accessible using a read-only SNMP community string. However, this MIB object lists the entire table of community strings, which are essentially passwords or keys used to control access to the SNMP interface. Because the read-only community string is commonly known or easily guessable, an attacker can retrieve the full list of community strings, including those with higher privileges. This exposure allows unauthorized users to gain sensitive information and potentially perform unauthorized management activities on the network device. The vulnerability is network exploitable without authentication and requires no user interaction, making it relatively easy to exploit. The CVSS v2 score is 7.5, reflecting its high impact on confidentiality, integrity, and availability. Although no patch is available, the vulnerability stems from insecure SNMP configuration and design flaws in the MIB implementation of this legacy network device.

For European organizations, this vulnerability poses a significant risk to network infrastructure security, especially for those still operating legacy 3Com SuperStack II hubs or similar devices. Exploitation could lead to unauthorized disclosure of SNMP community strings, enabling attackers to manipulate network device configurations, disrupt network operations, or intercept sensitive network management data. This could result in network downtime, data breaches, and loss of control over critical network components. Given that many industrial, governmental, and enterprise networks in Europe may still have legacy equipment in place, the threat could impact operational continuity and compliance with data protection regulations such as GDPR if sensitive data is exposed or network integrity is compromised.

Since no official patch is available for this vulnerability, European organizations should take immediate steps to mitigate risk. First, disable SNMP on affected 3Com SuperStack II hubs if it is not strictly necessary. If SNMP is required, restrict SNMP access to trusted management hosts using access control lists (ACLs) or network segmentation to limit exposure. Change default or well-known read-only community strings to complex, unique values and avoid using default community strings like 'public' or 'private'. Monitor network traffic for unusual SNMP queries that may indicate reconnaissance attempts. Consider replacing legacy 3Com SuperStack II hubs with modern, supported network devices that implement secure SNMP versions (e.g., SNMPv3) with strong authentication and encryption. Additionally, conduct regular network device audits to identify and remediate insecure configurations.