CVE-2022-35894 is a medium-severity vulnerability affecting Insyde InsydeH2O firmware versions with kernel 5.0 through 5.5. The vulnerability arises from the SMI (System Management Interrupt) handler for the FwBlockServiceSmm driver, which improperly uses an untrusted pointer as the destination for copying data. This flaw allows an attacker to specify a buffer location that the handler will write to, leading to unauthorized disclosure of sensitive information from the system memory. The vulnerability is rooted in insecure handling of pointers within the System Management Mode (SMM) environment, which operates at a high privilege level below the operating system, making exploitation potentially impactful. The CVSS 3.1 base score is 6.0, reflecting a medium severity level, with the vector indicating local attack vector (AV:L), low attack complexity (AC:L), high privileges required (PR:H), no user interaction (UI:N), scope changed (S:C), and high confidentiality impact (C:H) but no integrity or availability impact (I:N/A:N). The vulnerability does not require user interaction but does require high privileges, limiting the attack surface to local privileged users or processes. No known exploits in the wild have been reported, and no patches or vendor advisories are currently linked. The weakness is related to CWE-401, which typically refers to improper management of memory or resources, here manifesting as unsafe pointer usage leading to information disclosure.

For European organizations, this vulnerability poses a risk primarily to devices and systems utilizing Insyde InsydeH2O firmware versions 5.0 to 5.5, commonly found in laptops, embedded systems, and other computing devices. Successful exploitation could lead to leakage of sensitive information from protected system memory areas, potentially exposing cryptographic keys, credentials, or other confidential data. Given that the vulnerability requires local high privileges, the threat is more significant in environments where attackers can gain or escalate local access, such as through insider threats, compromised accounts, or lateral movement within networks. The confidentiality breach could undermine data protection obligations under GDPR, leading to regulatory and reputational consequences. Moreover, the SMM's privileged nature means that compromised firmware integrity could facilitate further attacks or persistence mechanisms. European organizations with high-value intellectual property, critical infrastructure, or sensitive personal data are particularly at risk if their hardware uses the affected firmware versions and if local privilege escalation is feasible.

To mitigate this vulnerability, European organizations should first identify devices running Insyde InsydeH2O firmware versions 5.0 through 5.5. Since no patches are currently linked, organizations should monitor Insyde's official channels for firmware updates addressing this issue and apply them promptly once available. In the interim, organizations should enforce strict access controls to limit local administrative privileges and prevent unauthorized users from gaining elevated access. Employing endpoint detection and response (EDR) solutions to monitor for suspicious local activity and potential exploitation attempts is advisable. Additionally, organizations should consider implementing hardware-based security features such as Intel Boot Guard or TPM to protect firmware integrity. Regular firmware integrity checks and secure boot configurations can help detect unauthorized modifications. Finally, educating users and administrators about the risks of local privilege escalation and enforcing least privilege principles will reduce the likelihood of exploitation.