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7.1
HIGH CVSS 3.1
CVE-2026-53187
RDMA/core: Validate cpu_id against nr_cpu_ids in DMAH alloc
Overview
Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Validate cpu_id against nr_cpu_ids in DMAH alloc The cpu_id attribute supplied by user space through UVERBS_ATTR_ALLOC_DMAH_CPU_ID is passed directly to cpumask_test_cpu() without first verifying that the value is within the valid CPU range. Passing such untrusted data to cpumask_test_cpu() may lead to an out-of-bounds read of the underlying cpumask bitmap: the helper expands to a test_bit() that indexes the bitmap by cpu_id / BITS_PER_LONG with no bound check. In addition, on kernels built with CONFIG_DEBUG_PER_CPU_MAPS it trips the WARN_ON_ONCE() in cpumask_check(); combined with panic_on_warn this turns a bad user input into a machine reboot. Reject any cpu_id that is not smaller than nr_cpu_ids with -EINVAL before it is used. Reported by Smatch.

Details
INFO

Published Date :

June 25, 2026, 9:16 a.m.

Last Modified :

July 6, 2026, 12:41 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Impact
Affected Products

The following products are affected by CVE-2026-53187 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
: Total Affected Vendor : 1 | Products : 1
Scoring
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
Validate cpu_id against nr_cpu_ids to prevent out-of-bounds reads and potential crashes.
  • Reject cpu_id not smaller than nr_cpu_ids.
  • Validate input data against CPU range.
  • Apply kernel patches to fix the issue.
References
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-2026-53187.

URL Resource
https://git.kernel.org/stable/c/0efbb6b54ff56300867027d8e0800d0e32226a20 Patch
https://git.kernel.org/stable/c/323c98a4ff06aa28114f2bf658fb43eb3b536bbc Patch
https://git.kernel.org/stable/c/bd5e818be7964c1689fba2dad9e6bd3a827fee74 Patch
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-53187 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-2026-53187 weaknesses.

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-2026-53187 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2026-53187 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.

  • Initial Analysis by [email protected]

    Jul. 06, 2026

    Action Type Old Value New Value
    Added CWE CWE-787
    Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.13 *cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.17 up to (excluding) 6.18.36
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/0efbb6b54ff56300867027d8e0800d0e32226a20 Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/323c98a4ff06aa28114f2bf658fb43eb3b536bbc Types: Patch
    Added Reference Type kernel.org: https://git.kernel.org/stable/c/bd5e818be7964c1689fba2dad9e6bd3a827fee74 Types: Patch
  • CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 28, 2026

    Action Type Old Value New Value
    Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Jun. 25, 2026

    Action Type Old Value New Value
    Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'd83edab562a496a42720902a1d2effccd05c37c5', 'lessThan': 'bd5e818be7964c1689fba2dad9e6bd3a827fee74', 'versionType': 'git'}, {'status': 'affected', 'version': 'd83edab562a496a42720902a1d2effccd05c37c5', 'lessThan': '0efbb6b54ff56300867027d8e0800d0e32226a20', 'versionType': 'git'}, {'status': 'affected', 'version': 'd83edab562a496a42720902a1d2effccd05c37c5', 'lessThan': '323c98a4ff06aa28114f2bf658fb43eb3b536bbc', 'versionType': 'git'}], 'programFiles': ['drivers/infiniband/core/uverbs_std_types_dmah.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.17'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.17', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.36', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.13', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['drivers/infiniband/core/uverbs_std_types_dmah.c'], 'defaultStatus': 'affected'}]
    Added Description In the Linux kernel, the following vulnerability has been resolved: RDMA/core: Validate cpu_id against nr_cpu_ids in DMAH alloc The cpu_id attribute supplied by user space through UVERBS_ATTR_ALLOC_DMAH_CPU_ID is passed directly to cpumask_test_cpu() without first verifying that the value is within the valid CPU range. Passing such untrusted data to cpumask_test_cpu() may lead to an out-of-bounds read of the underlying cpumask bitmap: the helper expands to a test_bit() that indexes the bitmap by cpu_id / BITS_PER_LONG with no bound check. In addition, on kernels built with CONFIG_DEBUG_PER_CPU_MAPS it trips the WARN_ON_ONCE() in cpumask_check(); combined with panic_on_warn this turns a bad user input into a machine reboot. Reject any cpu_id that is not smaller than nr_cpu_ids with -EINVAL before it is used. Reported by Smatch.
    Added Reference https://git.kernel.org/stable/c/0efbb6b54ff56300867027d8e0800d0e32226a20
    Added Reference https://git.kernel.org/stable/c/323c98a4ff06aa28114f2bf658fb43eb3b536bbc
    Added Reference https://git.kernel.org/stable/c/bd5e818be7964c1689fba2dad9e6bd3a827fee74
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.
CVSS
Vulnerability Scoring Details
Base CVSS Score: 7.1
Attack Vector
Attack Complexity
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Scope
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Integrity Impact
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