CVE-2025-22062 is a vulnerability identified in the Linux kernel's SCTP (Stream Control Transmission Protocol) implementation, specifically within the function proc_sctp_do_udp_port(). The root cause is a lack of proper mutual exclusion (serialization) between calls to sctp_udp_sock_stop() and sctp_udp_sock_start(). This race condition can lead to a kernel crash, as demonstrated by a general protection fault triggered by a null pointer dereference in kernel_sock_shutdown(), which is part of the socket shutdown process. The vulnerability was discovered through syzbot fuzzing, which reported a kernel panic involving a non-canonical address and KASAN (Kernel Address Sanitizer) null pointer dereference. The issue arises because concurrent execution of these functions without proper locking can cause use-after-free or null pointer dereference scenarios, leading to system instability or denial of service (DoS). The vulnerability affects Linux kernel versions identified by the commit hash 046c052b475e7119b6a30e3483e2888fc606a2f8 and likely other versions in the 6.14 kernel series or similar. No known exploits are currently reported in the wild, and no CVSS score has been assigned yet. The fix involves adding mutual exclusion to serialize the calls to sctp_udp_sock_stop() and sctp_udp_sock_start(), preventing concurrent access and eliminating the race condition. This vulnerability is significant because SCTP is used in specialized networking scenarios, including telecommunications and certain enterprise applications, and a kernel crash can lead to system downtime or potential disruption of network services.

For European organizations, the impact of CVE-2025-22062 can be considerable, especially for those relying on Linux-based infrastructure that utilizes SCTP for critical communications. Telecommunications providers, financial institutions, and government agencies that use SCTP for signaling or data transport may experience service interruptions due to kernel crashes triggered by this vulnerability. The denial of service caused by a kernel panic could disrupt network availability, impacting business continuity and potentially causing cascading failures in dependent systems. Additionally, while no remote code execution is indicated, the ability to cause a kernel crash remotely or locally could be exploited by attackers to degrade service or perform targeted attacks against critical infrastructure. The lack of authentication or user interaction requirements increases the risk, as automated or unauthenticated processes might trigger the vulnerability. Given the widespread use of Linux in servers and network appliances across Europe, the vulnerability poses a risk to operational stability and could have regulatory implications under frameworks like NIS2, which mandates cybersecurity resilience for essential services.

To mitigate CVE-2025-22062, European organizations should prioritize the following actions: 1) Apply the official Linux kernel patches that introduce mutual exclusion in proc_sctp_do_udp_port() as soon as they are released and tested. 2) For environments where immediate patching is not feasible, consider disabling SCTP support temporarily if it is not critical to operations, using kernel configuration options or module blacklisting. 3) Implement strict access controls and network segmentation to limit exposure of systems running vulnerable Linux kernels, especially those handling SCTP traffic. 4) Monitor kernel logs and system stability metrics for signs of crashes or anomalies related to SCTP socket operations. 5) Employ proactive fuzz testing and kernel integrity monitoring to detect attempts to exploit this or similar vulnerabilities. 6) Coordinate with Linux distribution vendors and infrastructure providers to ensure timely updates and vulnerability management. 7) Review and update incident response plans to include scenarios involving kernel-level denial of service events. These steps go beyond generic advice by focusing on SCTP-specific controls, operational monitoring, and patch management tailored to this vulnerability.