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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-6386 Detail

Description

In order to apply a particular protection key to an address range, the kernel must update the corresponding page table entries. The subroutine which handled this failed to take into account the presence of 1GB largepage mappings created using the shm_create_largepage(3) interface. In particular, it would always treat a page directory page entry as pointing to another page table page. The bug can be abused by an unprivileged user to cause pmap_pkru_update_range() to treat userspace memory as a page table page, and thus overwrite memory to which the application would otherwise not have access.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://security.freebsd.org/advisories/FreeBSD-SA-26:11.amd64.asc FreeBSD

Weakness Enumeration

CWE-ID CWE Name Source
CWE-269 Improper Privilege Management FreeBSD  
CWE-732 Incorrect Permission Assignment for Critical Resource FreeBSD  

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-6386
NVD Published Date:
04/21/2026
NVD Last Modified:
04/22/2026
Source:
FreeBSD