CVE-2022-48831 is a vulnerability identified in the Linux kernel's Integrity Measurement Architecture (IMA) subsystem, specifically within the asymmetric_verify() function. The flaw involves a reference leak related to cryptographic key handling. When the algorithm associated with a key is unknown, the function improperly leaks a reference to that key instead of correctly releasing it. This reference leak could potentially lead to resource exhaustion or unintended retention of sensitive cryptographic material in kernel memory. Although the vulnerability does not directly enable code execution or privilege escalation, improper management of cryptographic keys can undermine the integrity guarantees provided by IMA, which is used to ensure that only trusted code is executed on a system. The vulnerability was addressed by fixing the reference leak, ensuring that keys with unknown algorithms do not remain referenced improperly. The affected versions are identified by specific commit hashes, indicating that this is a recent and targeted fix in the Linux kernel source. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet.

For European organizations, the impact of CVE-2022-48831 primarily concerns systems relying on Linux kernels with IMA enabled for security-critical environments. IMA is often used in government, defense, financial institutions, and critical infrastructure sectors to enforce integrity policies. A reference leak in asymmetric_verify() could lead to gradual resource depletion, potentially causing denial of service or degraded system performance over time. Additionally, the improper handling of cryptographic keys might weaken the trust model of IMA, potentially allowing attackers to bypass integrity checks if combined with other vulnerabilities. Although exploitation requires specific conditions and does not appear straightforward, organizations with high security requirements could face increased risk if this vulnerability is left unpatched. The absence of known exploits reduces immediate risk, but the vulnerability's presence in the kernel code base means that attackers could develop exploits in the future, especially targeting systems with strict integrity enforcement.

European organizations should promptly apply the Linux kernel patches that address CVE-2022-48831. Since the fix is tied to specific commits, organizations should track their Linux distributions for updated kernel packages incorporating this patch. For environments using custom or long-term support kernels, backporting the fix is recommended. Additionally, organizations should audit their use of IMA and asymmetric key algorithms to ensure no unsupported or unknown algorithms are in use, reducing the chance of triggering the vulnerable code path. Monitoring system logs for unusual IMA-related errors or resource leaks can help detect exploitation attempts or related issues. Employing kernel integrity monitoring and maintaining strict access controls on systems running IMA will further reduce risk. Finally, organizations should maintain an up-to-date inventory of Linux kernel versions in use to prioritize patching efforts.