x86/mtrr: Check if fixed MTRRs exist before saving them
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 2.6.22 and later | 4.19.320, 5.4.282, 5.10.224, 5.15.165, 6.1.105, 6.6.46, 6.10.5, 6.11 | Patch available | CNA |
- Linux VendorLinux Affected 2.6.22 and later Fixed in 4.19.320, 5.4.282, 5.10.224, 5.15.165, 6.1.105, 6.6.46, 6.10.5, 6.11 Patch available CNA
CPE configurations NVD · 3
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 2.6.22 to before 4.19.320; 4.20 to before 5.4.282; 5.5 to before 5.10.224; 5.11 to before 5.15.165; 5.16 to before 6.1.105; 6.2 to before 6.6.46; 6.7 to before 6.10.5 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.11:rc1:*:*:*:*:*:* | 6.11 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.11:rc2:*:*:*:*:*:* | 6.11 rc2 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 2.6.22 to before 4.19.320; 4.20 to before 5.4.282; 5.5 to before 5.10.224; 5.11 to before 5.15.165; 5.16 to before 6.1.105; 6.2 to before 6.6.46; 6.7 to before 6.10.5 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.11:rc1:*:*:*:*:*:* Versions 6.11 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.11:rc2:*:*:*:*:*:* Versions 6.11 rc2 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 4.19.320, 5.4.282, 5.10.224, 5.15.165, 6.1.105, 6.6.46, 6.10.5, 6.11
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
Not affected: 4 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2024-44948
- 2026-10-03 Alias added: GHSA-7p6j-4w59-cjvv
References
Patch 8
- https://git.kernel.org/stable/c/34f36e6ee5bd7eff8b2adcd9fcaef369f752d82e
- https://git.kernel.org/stable/c/06c1de44d378ec5439db17bf476507d68589bfe9
- https://git.kernel.org/stable/c/450b6b22acdaac67a18eaf5ed498421ffcf10051
- https://git.kernel.org/stable/c/ca7d00c5656d1791e28369919e3e10febe9c3b16
- https://git.kernel.org/stable/c/8aa79dfb216b865e96ff890bc4ea71650f9bc8d7
- https://git.kernel.org/stable/c/8a90d3fc7c24608548d3a750671f9dac21d1a462
- https://git.kernel.org/stable/c/388f1c954019f253a8383f7eb733f38d541e10b6
- https://git.kernel.org/stable/c/919f18f961c03d6694aa726c514184f2311a4614
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2024-44948 · CVE Program
- CVE-2024-44948 · NVD
- FIRST EPSS
- GHSA-7p6j-4w59-cjvv · GitHub Advisory Database · CC BY 4.0
- CVE-2024-44948 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences