In the Linux kernel, the following vulnerability has been resolved: x86/mtrr: Check if fixed MTRRs exist before saving them MTRRs have an obsolete fixed variant for fine grained caching control of the 640K-1MB region that uses separate MSRs. This fixed variant has a separate capability bit in the MTRR capability MSR. So far all x86 CPUs which support MTRR have this separate bit set, so it went unnoticed that mtrr_save_state() does not check the capability bit before accessing the fixed MTRR MSRs. Though on a CPU that does not support the fixed MTRR capability this results in a #GP. The #GP itself is harmless because the RDMSR fault is handled gracefully, but results in a WARN_ON(). Add the missing capability check to prevent this.

Metrics

No CVSS v4.0

Attack Vector Local

Attack Complexity Low

Privileges Required Low

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploitation none

Automatable no

Technical Impact partial

Affected Vendors & Products

No data.

No data.

No data.

References
Link Providers
https://git.kernel.org/stable/c/06c1de44d378ec5439db17bf476507d68589bfe9 cve-icon cve-icon
https://git.kernel.org/stable/c/34f36e6ee5bd7eff8b2adcd9fcaef369f752d82e cve-icon cve-icon
https://git.kernel.org/stable/c/388f1c954019f253a8383f7eb733f38d541e10b6 cve-icon cve-icon
https://git.kernel.org/stable/c/450b6b22acdaac67a18eaf5ed498421ffcf10051 cve-icon cve-icon
https://git.kernel.org/stable/c/8a90d3fc7c24608548d3a750671f9dac21d1a462 cve-icon cve-icon
https://git.kernel.org/stable/c/8aa79dfb216b865e96ff890bc4ea71650f9bc8d7 cve-icon cve-icon
https://git.kernel.org/stable/c/919f18f961c03d6694aa726c514184f2311a4614 cve-icon cve-icon
https://git.kernel.org/stable/c/ca7d00c5656d1791e28369919e3e10febe9c3b16 cve-icon cve-icon
https://lore.kernel.org/linux-cve-announce/2024090407-CVE-2024-44948-5554@gregkh/T cve-icon
https://nvd.nist.gov/vuln/detail/CVE-2024-44948 cve-icon
https://www.cve.org/CVERecord?id=CVE-2024-44948 cve-icon
History

Wed, 09 Oct 2024 14:45:00 +0000

Type Values Removed Values Added
Weaknesses CWE-754

Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Wed, 04 Sep 2024 23:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

 cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate

Wed, 04 Sep 2024 18:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: x86/mtrr: Check if fixed MTRRs exist before saving them MTRRs have an obsolete fixed variant for fine grained caching control of the 640K-1MB region that uses separate MSRs. This fixed variant has a separate capability bit in the MTRR capability MSR. So far all x86 CPUs which support MTRR have this separate bit set, so it went unnoticed that mtrr_save_state() does not check the capability bit before accessing the fixed MTRR MSRs. Though on a CPU that does not support the fixed MTRR capability this results in a #GP. The #GP itself is harmless because the RDMSR fault is handled gracefully, but results in a WARN_ON(). Add the missing capability check to prevent this.
Title x86/mtrr: Check if fixed MTRRs exist before saving them
References
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-09-04T18:35:48.980Z

Updated: 2024-11-05T09:42:44.546Z

Reserved: 2024-08-21T05:34:56.665Z

Link: CVE-2024-44948

cve-icon Vulnrichment

Updated: 2024-09-11T12:42:27.703Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-09-04T19:15:29.950

Modified: 2024-09-05T12:53:21.110

Link: CVE-2024-44948

cve-icon Redhat

Severity : Moderate

Publid Date: 2024-09-04T00:00:00Z

Links: CVE-2024-44948 - Bugzilla