7.1
HIGH
CVE-2021-47327
Linux Kernel ARM SMMU Reference Counting Leak
Description

In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the refcount of the "smmu" even though the return value is less than 0. The reference counting issue happens in some error handling paths of arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get() fails, the caller functions forget to decrease the refcount of "smmu" increased by arm_smmu_rpm_get(), causing a refcount leak. Fix this issue by calling pm_runtime_resume_and_get() instead of pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount balanced in case of failure.

INFO

Published Date :

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

Last Modified :

July 3, 2024, 1:37 a.m.

Source :

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

Remotely Exploitable :

No

Impact Score :

5.2

Exploitability Score :

1.8
Affected Products

The following products are affected by CVE-2021-47327 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

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-2021-47327 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2021-47327 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 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 03, 2024

    Action Type Old Value New Value
    Added CWE CISA-ADP CWE-911
    Added CVSS V3.1 CISA-ADP AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
  • 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: iommu/arm-smmu: Fix arm_smmu_device refcount leak when arm_smmu_rpm_get fails arm_smmu_rpm_get() invokes pm_runtime_get_sync(), which increases the refcount of the "smmu" even though the return value is less than 0. The reference counting issue happens in some error handling paths of arm_smmu_rpm_get() in its caller functions. When arm_smmu_rpm_get() fails, the caller functions forget to decrease the refcount of "smmu" increased by arm_smmu_rpm_get(), causing a refcount leak. Fix this issue by calling pm_runtime_resume_and_get() instead of pm_runtime_get_sync() in arm_smmu_rpm_get(), which can keep the refcount balanced in case of failure.
    Added Reference kernel.org https://git.kernel.org/stable/c/3761ae0d0e549f2acdaf11f49df4ed06d256b20f [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/c4007596fbdabc29f858dc2e1990858a146b60b2 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/fbf4daa6f4105e01fbd3868006f65c163365c1e3 [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/fe92c058199067ae90cf2a901ddf3c271893557a [No types assigned]
    Added Reference kernel.org https://git.kernel.org/stable/c/1adf30f198c26539a62d761e45af72cde570413d [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-2021-47327 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-2021-47327 weaknesses.

CVSS31 - Vulnerability Scoring System
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