CVE-2025-35998: Intel QAT Privilege Escalation Flaw

CVE-2025-35998 Overview

CVE-2025-35998 is a privilege escalation vulnerability affecting Intel Quick Assist Technology (QAT) for certain Intel platforms. The vulnerability stems from a missing protection mechanism for an alternate hardware interface within Ring 0 (Kernel level). A system software adversary with privileged access can exploit this flaw through local access with low attack complexity, potentially escalating their privileges on the vulnerable system.

Critical Impact

This vulnerability enables privilege escalation through exploitation of unprotected alternate hardware interfaces in Intel QAT at the kernel level, potentially compromising system confidentiality and integrity.

Affected Products

• Intel Quick Assist Technology for Intel Platforms (Ring 0: Kernel)
• Intel platforms utilizing QAT hardware acceleration
• Systems with Intel QAT drivers operating at kernel level

Discovery Timeline

• 2026-02-10 - CVE CVE-2025-35998 published to NVD
• 2026-02-10 - Last updated in NVD database

Technical Details for CVE-2025-35998

Vulnerability Analysis

This vulnerability is classified under CWE-1299 (Missing Protection Mechanism for Alternate Hardware Interface). The flaw exists within Intel Quick Assist Technology's kernel-level implementation, where an alternate hardware interface lacks adequate protection mechanisms. The exploitation requires local access with privileged user permissions, though the attack complexity itself is considered low once access is obtained.

The vulnerability requires specific attack prerequisites to be present and demands specialized internal knowledge of the target system. While no user interaction is needed for exploitation, the attacker must already possess elevated privileges on the system. Successful exploitation can result in high impact to system confidentiality and integrity, though availability is not affected.

Root Cause

The root cause is a missing protection mechanism for an alternate hardware interface in Intel QAT's Ring 0 kernel implementation. This architectural oversight allows privileged attackers with specific knowledge of the hardware interface to bypass intended security boundaries, accessing functionality that should be protected at the kernel level.

Attack Vector

The attack vector is local, requiring the adversary to have existing privileged access to the target system. The attacker leverages the unprotected alternate hardware interface to escalate their privileges beyond their current authorization level. While the attack complexity is low, it requires:

• Local access to the vulnerable system
• Existing privileged user account
• Knowledge of specific attack requirements and internal system details
• No user interaction needed

The vulnerability mechanism involves directly interacting with the unprotected hardware interface at the kernel level. For detailed technical information on the exploitation path, refer to the Intel Security Advisory SA-01406.

Detection Methods for CVE-2025-35998

Indicators of Compromise

• Unusual kernel-level access patterns to Intel QAT hardware interfaces
• Unexpected privilege elevation events from processes interacting with QAT drivers
• Anomalous system calls targeting QAT hardware components
• Evidence of unauthorized access to Ring 0 kernel resources

Detection Strategies

• Monitor for suspicious kernel-level activity involving Intel QAT drivers and hardware interfaces
• Implement kernel-level auditing for QAT-related system calls and hardware interactions
• Deploy endpoint detection solutions capable of identifying privilege escalation attempts
• Review system logs for evidence of unauthorized access to hardware acceleration features

Monitoring Recommendations

• Enable comprehensive logging for Intel QAT driver operations and hardware interactions
• Configure security information and event management (SIEM) rules to alert on privilege escalation indicators
• Implement behavioral analysis for processes with QAT hardware access
• Regularly audit user accounts with privileged access to systems running Intel QAT

How to Mitigate CVE-2025-35998

Immediate Actions Required

• Review the Intel Security Advisory SA-01406 for vendor-specific guidance
• Audit systems for Intel QAT deployments and identify vulnerable configurations
• Restrict privileged access to systems running Intel Quick Assist Technology
• Implement the principle of least privilege for accounts with access to QAT-enabled systems

Patch Information

Intel has addressed this vulnerability in Security Advisory SA-01406. Organizations should consult the Intel Security Advisory SA-01406 for specific patch information, including updated driver versions and firmware updates for affected platforms.

Workarounds

• Limit local access to systems with Intel QAT to only essential personnel
• Implement strict access controls and monitoring for privileged accounts
• Consider disabling Intel QAT functionality on systems where it is not critical until patches can be applied
• Segment QAT-enabled systems from less trusted network environments

# Configuration example
# Review current Intel QAT driver status
lsmod | grep qat

# Check QAT device status (if available)
systemctl status qat

# Restrict access to QAT devices (example permission hardening)
chmod 600 /dev/qat*
chown root:root /dev/qat*