0.0
NA
CVE-2021-47429
PowerPC Linux Kernel NMI-Triggered Machine Check Handler Vulnerability
Description

In the Linux kernel, the following vulnerability has been resolved: powerpc/64s: Fix unrecoverable MCE calling async handler from NMI The machine check handler is not considered NMI on 64s. The early handler is the true NMI handler, and then it schedules the machine_check_exception handler to run when interrupts are enabled. This works fine except the case of an unrecoverable MCE, where the true NMI is taken when MSR[RI] is clear, it can not recover, so it calls machine_check_exception directly so something might be done about it. Calling an async handler from NMI context can result in irq state and other things getting corrupted. This can also trigger the BUG at arch/powerpc/include/asm/interrupt.h:168 BUG_ON(!arch_irq_disabled_regs(regs) && !(regs->msr & MSR_EE)); Fix this by making an _async version of the handler which is called in the normal case, and a NMI version that is called for unrecoverable interrupts.

INFO

Published Date :

May 21, 2024, 3:15 p.m.

Last Modified :

May 21, 2024, 4:53 p.m.

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67

Remotely Exploitable :

No

Impact Score :

Exploitability Score :

Affected Products

The following products are affected by CVE-2021-47429 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Linux linux_kernel
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-47429.

URL Resource
https://git.kernel.org/stable/c/d7a8e38999fbd6910516e44cb43f9f4317e54f73
https://git.kernel.org/stable/c/f08fb25bc66986b0952724530a640d9970fa52c1

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-47429 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-47429 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 28, 2024

    Action Type Old Value New Value
  • CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    May. 21, 2024

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: powerpc/64s: Fix unrecoverable MCE calling async handler from NMI The machine check handler is not considered NMI on 64s. The early handler is the true NMI handler, and then it schedules the machine_check_exception handler to run when interrupts are enabled. This works fine except the case of an unrecoverable MCE, where the true NMI is taken when MSR[RI] is clear, it can not recover, so it calls machine_check_exception directly so something might be done about it. Calling an async handler from NMI context can result in irq state and other things getting corrupted. This can also trigger the BUG at arch/powerpc/include/asm/interrupt.h:168 BUG_ON(!arch_irq_disabled_regs(regs) && !(regs->msr & MSR_EE)); Fix this by making an _async version of the handler which is called in the normal case, and a NMI version that is called for unrecoverable interrupts.
    Added Reference kernel.org https://git.kernel.org/stable/c/d7a8e38999fbd6910516e44cb43f9f4317e54f73 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/f08fb25bc66986b0952724530a640d9970fa52c1 [No types assigned]
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-47429 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-47429 weaknesses.

NONE - Vulnerability Scoring System