CVE-2018-12130 in Intel
Summary
by MITRE
Microarchitectural Fill Buffer Data Sampling (MFBDS): Fill buffers on some microprocessors utilizing speculative execution may allow an authenticated user to potentially enable information disclosure via a side channel with local access. A list of impacted products can be found here: https://www.intel.com/content/dam/www/public/us/en/documents/corporate-information/SA00233-microcode-update-guidance_05132019.pdf
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Analysis
by VulDB Data Team • 05/30/2026
The vulnerability identified as CVE-2018-12130 represents a significant microarchitectural flaw that affects Intel processors utilizing speculative execution mechanisms. This vulnerability falls under the broader category of microarchitectural data sampling issues that exploit the inherent design characteristics of modern processor architectures. The flaw specifically targets fill buffers within the processor's microarchitecture, which are responsible for managing data flow during speculative execution phases. These buffers serve as temporary storage locations that hold data while the processor speculatively executes instructions before confirming whether those execution paths are valid. The vulnerability arises from insufficient isolation between speculative and non-speculative execution contexts, creating potential information leakage pathways.
The technical implementation of this vulnerability stems from how fill buffers handle data during the speculative execution process. When a processor speculatively executes instructions, it may store intermediate data in fill buffers before the actual execution path is confirmed. The flaw occurs because this speculative data can be accessed through side channel attacks, allowing an authenticated user to potentially extract sensitive information from these buffers. The vulnerability requires local access and authentication to exploit, but the implications are severe as it enables information disclosure through sophisticated side channel techniques. The attack vector leverages the processor's microarchitectural behavior to infer sensitive data that should remain isolated during speculative execution phases.
The operational impact of CVE-2018-12130 extends beyond simple information disclosure, as it represents a fundamental weakness in processor security architecture that affects multiple generations of Intel processors. This vulnerability contributes to the broader class of Meltdown and Spectre family attacks, sharing similar underlying architectural weaknesses in speculative execution handling. The implications for system security are substantial, as it allows for potential extraction of cryptographic keys, passwords, and other sensitive data that might be stored in processor buffers during speculative execution. Organizations utilizing affected processors must consider the comprehensive security implications across their entire infrastructure, as this vulnerability can affect virtualized environments, cloud deployments, and traditional on-premises systems alike. The vulnerability's impact is particularly concerning because it operates at the microarchitectural level, making it difficult to detect and mitigate through traditional software-based approaches.
Mitigation strategies for CVE-2018-12130 primarily involve microcode updates provided by Intel, which modify processor behavior to prevent the information leakage through fill buffers. The recommended approach includes implementing the latest microcode updates from Intel, which address the vulnerability through architectural modifications that enhance isolation between speculative and non-speculative execution contexts. Organizations should also consider operating system-level mitigations such as kernel page table isolation and other software-based protections that work in conjunction with microcode updates. The mitigation process requires careful planning due to potential performance impacts, as these security measures can introduce overhead that affects system throughput. Compliance with industry standards such as those outlined in the Common Weakness Enumeration (CWE) classification for microarchitectural vulnerabilities and ATT&CK framework techniques related to privilege escalation and information disclosure is essential for comprehensive security posture management. Additionally, organizations should implement monitoring and detection capabilities to identify potential exploitation attempts and maintain awareness of related vulnerabilities in the same vulnerability family that may require similar mitigation approaches.