CVE-2025-6549 is an Incorrect Authorization vulnerability (CWE-863) found in the web server component of Juniper Networks Junos OS running on SRX Series devices. The vulnerability arises when Juniper Secure Connect (JSC) is enabled on specific interfaces or when multiple interfaces are configured for the Juniper Web Device Manager (J-Web). Under these conditions, the J-Web UI becomes accessible over more network interfaces than intended, allowing an unauthenticated, network-based attacker to reach the management interface without proper authorization. This exposure can lead to unauthorized access to the device's web management interface, potentially enabling attackers to gather sensitive information or attempt further exploitation. The vulnerability affects multiple versions of Junos OS, specifically all versions before 21.4R3-S9, 22.2 versions before 22.2R3-S5, 22.4 versions before 22.4R3-S5, 23.2 versions before 23.2R2-S3, 23.4 versions before 23.4R2-S5, and 24.2 versions before 24.2R2. The CVSS v3.1 base score is 6.5 (medium severity), reflecting that the vulnerability can be exploited remotely over the network without authentication or user interaction, with low complexity, and impacts confidentiality and integrity but not availability. No known exploits are currently reported in the wild. The core issue is an authorization bypass due to improper interface binding of the J-Web UI, which violates the principle of least privilege by exposing management interfaces beyond their intended scope.

For European organizations, this vulnerability poses a significant risk primarily to those deploying Juniper SRX Series devices running affected Junos OS versions. Unauthorized access to the J-Web management interface could allow attackers to gather sensitive configuration data, potentially leading to further compromise or lateral movement within the network. Confidentiality and integrity of network device configurations are at risk, which could undermine network security posture and trust. Although availability is not directly impacted, the exposure of management interfaces increases the attack surface and could facilitate subsequent attacks such as configuration manipulation or deployment of malicious firmware. Given the critical role of SRX devices in perimeter and internal network security, exploitation could affect sectors with high security requirements such as finance, telecommunications, government, and critical infrastructure within Europe. The medium severity rating suggests that while exploitation is feasible without authentication, the impact is somewhat limited to information disclosure and unauthorized access rather than immediate denial of service or full device takeover.

European organizations should prioritize upgrading affected Junos OS versions to the fixed releases specified by Juniper Networks (21.4R3-S9 or later, 22.2R3-S5 or later, 22.4R3-S5 or later, 23.2R2-S3 or later, 23.4R2-S5 or later, and 24.2R2 or later). Until patches are applied, administrators should review and restrict the interfaces on which J-Web is enabled, ensuring it is only accessible on trusted management networks and interfaces. Network segmentation and firewall rules should be implemented to block unauthorized access to J-Web interfaces from untrusted networks. Additionally, disable Juniper Secure Connect (JSC) on interfaces where it is not strictly required to reduce exposure. Monitoring and logging of access to the J-Web interface should be enhanced to detect any anomalous or unauthorized connection attempts. Employing multi-factor authentication (MFA) for management access, where supported, can further reduce risk. Regular audits of device configurations and interface bindings are recommended to ensure compliance with security policies.