CVE-2025-0647 is a vulnerability identified in Arm's Neoverse-N2 CPU architecture, classified under CWE-226 (Sensitive Information in Resource Not Removed Before Reuse). The issue stems from the interaction between the CPP RCTX instruction and the TLB invalidation mechanism. Normally, when a Translation Lookaside Buffer Invalidate (TLBI) instruction is issued to a Processing Element (PE), it clears stale TLB entries to maintain memory translation correctness and security. However, in affected Neoverse-N2 CPUs, executing a CPP RCTX instruction on one PE can inhibit this invalidation process when a TLBI is issued either by the same or another PE within the same shareability domain. This inhibition results in the PE retaining stale TLB entries that should have been invalidated. The stale entries may contain sensitive memory translation information, potentially allowing a privileged attacker to access or infer data from other processes or cores, violating confidentiality and integrity. The vulnerability requires privileged access (PR:H) and does not require user interaction (UI:N), but it affects the entire shareability domain (S:C), meaning the impact can cross processing elements. The CVSS v3.1 score of 7.9 reflects a high severity due to the significant confidentiality and integrity impacts, despite the limited attack vector (local privileged attacker). No public exploits are known at this time, and no patches have been linked yet, indicating that mitigation may rely on forthcoming microcode or firmware updates from Arm. This vulnerability is particularly relevant for multi-core server environments and cloud infrastructure where Neoverse-N2 CPUs are deployed, as it could allow sensitive data leakage between virtual machines or containers sharing the same physical hardware. The issue highlights the importance of correct TLB management in CPU architectures to prevent cross-core data leakage.

For European organizations, the impact of CVE-2025-0647 is significant in environments utilizing Arm Neoverse-N2 CPUs, which are increasingly adopted in cloud data centers, telecom infrastructure, and edge computing platforms. The vulnerability could allow attackers with elevated privileges to access sensitive information across processing elements, undermining data confidentiality and integrity. This is particularly critical for sectors handling sensitive personal data under GDPR, such as finance, healthcare, and government services. The flaw could facilitate cross-VM or cross-container data leakage in multi-tenant cloud environments, increasing the risk of insider threats or lateral movement by attackers. While availability is not directly impacted, the breach of confidentiality and integrity could lead to regulatory penalties, reputational damage, and loss of customer trust. Given the high reliance on Arm-based infrastructure in European telecom operators and cloud providers, the vulnerability poses a strategic risk. Organizations may face challenges in patching due to the need for firmware or microcode updates and potential downtime. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once patches are released.

European organizations should proactively engage with Arm and their hardware vendors to obtain and apply microcode or firmware updates addressing CVE-2025-0647 as soon as they become available. Until patches are deployed, enforcing strict access controls to limit privileged user access can reduce exploitation risk. Implementing robust monitoring for anomalous TLB or CPU behavior may help detect attempts to exploit the vulnerability. Virtualization and containerization platforms should be configured to isolate workloads and minimize shared resource exposure within the same shareability domain. Security teams should review and harden privilege escalation paths to prevent unauthorized privileged access. Where possible, organizations should evaluate the deployment of affected CPUs in sensitive environments and consider alternative hardware or architectures until mitigations are in place. Collaboration with cloud service providers to confirm patch status and mitigation strategies is advisable for customers relying on third-party infrastructure. Finally, updating incident response plans to include this vulnerability and educating relevant personnel about its risks will enhance preparedness.