CVE-2022-48654 is a medium-severity vulnerability found in the Linux kernel's netfilter subsystem, specifically within the nfnetlink_osf module. The vulnerability arises from a logic flaw in the nf_osf_find() function, which is responsible for matching certain network packets against expected criteria. Due to an incorrect implementation, nf_osf_find() may return a positive match even when there is a mismatch. This erroneous behavior leads to the copying of uninitialized kernel stack memory into the nft_osf data structures. Consequently, this can result in the leakage of stale kernel stack data to userspace processes. Such leakage can expose sensitive kernel memory contents, potentially including cryptographic keys, pointers, or other sensitive information residing temporarily on the kernel stack. The vulnerability requires local access with low privileges (PR:L) and does not require user interaction (UI:N). The attack vector is local (AV:L), meaning an attacker must have some level of access to the system to exploit this flaw. The vulnerability impacts confidentiality, integrity, and availability to a limited extent, as the leaked data could be used for further attacks or privilege escalation, but direct exploitation for system compromise is not straightforward. The CVSS v3.1 base score is 5.3, reflecting a medium severity. No known exploits in the wild have been reported to date. The vulnerability was publicly disclosed on April 28, 2024, and patches have been released to fix the logic error in nf_osf_find().

For European organizations, this vulnerability poses a risk primarily to systems running vulnerable Linux kernel versions that include the affected nfnetlink_osf module. Since Linux is widely used in servers, cloud infrastructure, and embedded devices across Europe, the potential for information leakage could impact confidentiality of sensitive data. Attackers with local access could exploit this flaw to glean kernel memory contents, which might aid in crafting further attacks such as privilege escalation or bypassing security controls. This is particularly concerning for organizations handling sensitive personal data under GDPR, critical infrastructure operators, and enterprises relying on Linux-based security appliances or network devices. However, the requirement for local access limits the threat to insiders, compromised accounts, or attackers who have already gained some foothold. The vulnerability could also affect cloud service providers and hosting environments in Europe, where multi-tenant Linux systems are common, potentially exposing data across tenants if exploited. Overall, the impact is moderate but should not be underestimated in environments where kernel memory confidentiality is critical.

European organizations should prioritize applying the official Linux kernel patches that address CVE-2022-48654 as soon as possible. Given the local access requirement, organizations should also strengthen access controls to limit who can execute code or commands on Linux systems, including enforcing strict user privilege separation and monitoring for suspicious local activity. Employing kernel hardening techniques such as Kernel Address Space Layout Randomization (KASLR) and enabling security modules like SELinux or AppArmor can reduce the risk of exploitation. Regularly auditing and updating Linux kernel versions to the latest stable releases will help mitigate this and other vulnerabilities. Network segmentation and restricting administrative access to critical Linux servers can further reduce exposure. For cloud environments, ensure tenant isolation and monitor for anomalous kernel memory access patterns. Finally, organizations should implement comprehensive logging and alerting to detect potential exploitation attempts early.