CERT/CC: VU#553437: InsydeH2O IHISI SMM is vulnerable to unsafe memory write operations
CERT/CC has published a new security advisory. Here is a summary and what to do.
Key points
- New advisory from CERT/CC.
- Review affected versions in the advisory.
- Apply updates promptly.
CERT/CC published a security advisory titled “VU#553437: InsydeH2O IHISI SMM is vulnerable to unsafe memory write operations”.
At a glance
- Publisher
- CERT/CC
- CVEs
- See advisory
What the advisory says
Overview An Out-of-bounds Write vulnerability in the InsydeH2O IHISI software used by HP PC BIOS can allow a local attacker with OS kernel privileges to perform arbitrary physical memory writes, including writes to System Management RAM (SMRAM). Because the vulnerable code executes in System Management Mode (SMM), successful exploitation can allow an attacker to modify SMM-protected memory and potentially achieve arbitrary code execution in SMM. Depending on the platform's memory and firmware configuration, the arbitrary physical memory write primitive may also have implications for UEFI firmware update or flash-related operations. Description HP PC BIOS is firmware that initializes and manages hardware components during the boot process and provides runtime services to the operating system and provide the ability to update firmware. The affected system uses InsydeH2O Kernel version 5.5
What should you do?
- Read the full vendor advisory linked below and confirm whether you run affected versions.
- Schedule the recommended update, prioritising internet-facing systems.
- Watch for exploitation reports; unpatched edge devices are frequent targets.
What to do and how to stay safe: CERT/CC
- Patch scores alone ignore context like network exposure and asset criticality.
- You must map vulnerabilities to specific business risks to prioritize correctly.
- Continuous exposure data replaces static scanning for accurate prioritization.
Prioritize vulnerabilities by actual exploitability and business impact, not by theoretical severity scores. Update your asset context and exposure data continuously to maintain accurate risk rankings.
Step-by-step guide: Risk Based Vulnerability Management: Prioritize Fixes by Actual Threat
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
