CVE-2026-20917 in Processors
Summary
by MITRE • 08/11/2026
Exposure of sensitive information caused by incorrect data forwarding during transient execution for some Intel(R) Processors within Ring 0: Hypervisor and Kernel may allow information disclosure. System software adversary with a privileged user combined with a high complexity attack may enable data exposure. This result may potentially occur via local access when attack requirements are not present without special internal knowledge and requires no user interaction. The potential vulnerability may impact the confidentiality (none), integrity (none) and availability (none) of the vulnerable system, resulting in subsequent system confidentiality (high), integrity (none) and availability (none) impacts.
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Analysis
by VulDB Data Team • 08/11/2026
This vulnerability represents a sophisticated information disclosure flaw that exploits transient execution mechanisms within Intel processors operating at Ring 0 privilege level. The issue manifests during data forwarding operations when hypervisor and kernel components interact with sensitive information, creating potential exposure pathways for unauthorized access. The vulnerability specifically affects Intel processor architectures where transient execution behaviors create opportunities for information leakage through improper data handling during system-level operations.
The technical flaw stems from incorrect data forwarding mechanisms that occur during transient execution phases, particularly when processors execute instructions speculatively before their actual execution context is fully determined. This creates a window where sensitive data may be inadvertently exposed through side-channel mechanisms or cache-based information leakage patterns. The vulnerability operates at the most privileged ring level, meaning it can potentially affect hypervisor and kernel components that handle critical system operations and confidential data processing.
Attackers with privileged user access combined with high complexity attack methods can exploit this weakness to gain unauthorized information disclosure capabilities. The attack requires local system access but does not necessitate user interaction or special internal knowledge beyond standard privileged access levels. This makes the vulnerability particularly concerning for environments where privilege escalation attacks are possible, as adversaries could leverage this weakness to extract sensitive data from system memory and kernel structures.
The operational impact of this vulnerability extends beyond simple information disclosure, potentially compromising system confidentiality at high severity levels while maintaining no direct impact on data integrity or system availability. The exposure occurs through transient execution pathways that may not be immediately apparent during normal system operation, making detection and mitigation particularly challenging for security teams. This type of vulnerability aligns with CWE-200 (Information Exposure) and represents a sophisticated exploitation vector that can be mapped to ATT&CK technique T1059.003 (Command and Scripting Interpreter: Windows Command Shell).
Mitigation strategies should focus on implementing comprehensive processor microcode updates from Intel, which address the underlying transient execution behaviors that create information exposure opportunities. System administrators must also consider hypervisor and kernel-level security configurations that limit data forwarding operations between privileged components. Additional defensive measures include memory protection mechanisms, cache management controls, and monitoring systems designed to detect anomalous data access patterns that could indicate exploitation attempts. Organizations should implement regular vulnerability assessments and maintain updated threat intelligence feeds to identify potential exploitation attempts targeting this specific class of transient execution vulnerabilities.