CVE-2022-48630 is a vulnerability identified in the Linux kernel's Qualcomm random number generator (qcom-rng) driver. The issue arises from a logic error introduced by a commit that removed a 'break' statement from the else branch in the qcom_rng_read() function. This removal causes the function to enter an infinite loop when the requested number of bytes ('max') is not a multiple of the system's word size (WORD_SZ). The infinite loop can be triggered by user-space applications making specific requests to the random number generator, such as invoking 'kcapi-rng -b 67'. The root cause is a control flow flaw that prevents the function from exiting correctly under certain input conditions. The vulnerability was tested on Qualcomm Amberwing processors, which are commonly used in embedded and mobile devices. The fix involves restoring the 'break' statement to ensure proper loop termination. This vulnerability affects multiple Linux kernel versions identified by specific commit hashes, indicating a range of affected kernel builds. There are no known exploits in the wild at this time, and no CVSS score has been assigned yet. The vulnerability impacts the availability of the random number generator service by causing it to hang indefinitely, potentially leading to denial of service conditions in affected systems.

For European organizations, this vulnerability primarily threatens the availability of systems running affected Linux kernel versions on Qualcomm-based hardware. Since the qcom-rng driver is responsible for providing entropy to cryptographic operations, an infinite loop could stall processes relying on randomness, potentially causing system hangs or degraded performance. This can impact embedded systems, IoT devices, and mobile infrastructure that use Qualcomm processors and Linux kernels with the vulnerable driver. Critical infrastructure relying on such devices for secure communications or cryptographic functions could experience service disruptions. Although the vulnerability does not directly expose confidentiality or integrity risks, the denial of service effect could indirectly impact business operations, especially in sectors like telecommunications, manufacturing, and automotive industries where Qualcomm processors are prevalent. The lack of known exploits reduces immediate risk, but the ease of triggering the infinite loop via user-space commands suggests that local attackers or malicious software could exploit this flaw to degrade system availability.

European organizations should prioritize patching affected Linux kernel versions by applying the fix that restores the 'break' statement in the qcom_rng_read() function. Kernel updates from trusted Linux distributions or direct kernel source patches should be deployed promptly on all Qualcomm-based devices. For embedded and IoT devices where kernel updates are challenging, organizations should consider implementing runtime monitoring to detect and recover from hung processes related to the RNG service. Limiting access to the random number generator device node (/dev/hwrng or equivalent) to trusted users and processes can reduce the risk of exploitation. Additionally, organizations should audit their device inventory to identify systems using Qualcomm Amberwing or similar processors with vulnerable kernels and prioritize remediation accordingly. Network segmentation and application whitelisting can help contain potential denial of service impacts. Finally, organizations should monitor vendor advisories and Linux kernel mailing lists for any emerging exploit reports or additional patches.