CVE-2025-54547 is a vulnerability classified under CWE-613 (Insufficient Session Expiration) affecting Arista Networks' DANZ Monitoring Fabric product. The issue arises when SSH session multiplexing is enabled on the client side, allowing multiple SSH sessions (such as scp or sftp) to share a single underlying channel. Due to improper handling of session timeouts, multiplexed sessions can continue to perform file-system operations even after the configured SSH session timeout has expired. This means that an attacker or user with access to an SSH session that should have timed out can still execute file operations, potentially leading to unauthorized data access or modification. The vulnerability requires that the attacker has at least limited privileges (PR:L) and local access to the SSH session, but no user interaction is needed. The CVSS 3.1 base score is 5.3, reflecting a medium severity with low attack vector (local), low attack complexity, and partial impact on confidentiality, integrity, and availability. No patches or known exploits are currently available, but the flaw represents a risk in environments where session multiplexing is used extensively for operational efficiency. This vulnerability highlights the importance of proper session lifecycle management in secure network device operations.

For European organizations, the impact of CVE-2025-54547 can be significant in environments where Arista DANZ Monitoring Fabric is deployed for network traffic monitoring and analysis. Unauthorized file-system operations after session timeout expiration could lead to data leakage, unauthorized modification of monitoring configurations or logs, and potential disruption of monitoring services. This can affect the confidentiality and integrity of sensitive network data and reduce the availability of monitoring capabilities critical for security operations. Organizations in sectors such as telecommunications, finance, critical infrastructure, and government that rely on Arista's monitoring solutions may face increased risk of insider threats or lateral movement by attackers exploiting this vulnerability. The medium severity score suggests that while the vulnerability is not trivially exploitable remotely, the consequences of exploitation could degrade network visibility and incident response effectiveness, thereby increasing overall organizational risk.

To mitigate CVE-2025-54547, European organizations should first audit their use of SSH session multiplexing on Arista DANZ Monitoring Fabric devices and consider disabling multiplexing if it is not essential. Where multiplexing is required, implement strict session management policies including reduced session timeout values and enhanced monitoring of SSH session activity to detect anomalous file operations post-timeout. Network segmentation and access controls should limit SSH access to trusted administrators only. Employ multi-factor authentication and role-based access controls to minimize the risk of privilege misuse. Additionally, maintain up-to-date device firmware and subscribe to Arista security advisories for forthcoming patches addressing this vulnerability. Implement logging and alerting mechanisms to capture unusual SSH session behaviors indicative of exploitation attempts. Finally, conduct regular security training for administrators on secure SSH usage and session management best practices.