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CVE-2024-50115

HIGHCVSS 7.1/10EPSS 0.24%

Last modified

CVE-2024-50115 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits 4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't enforce 32-byte alignment of nCR3. In the absolute worst case scenario, failure to ignore bits 4:0 can result in an out-of-bounds read, e.g. if the target page is at the end of a memslot, and the VMM isn't using guard pages. Per the APM: The CR3 register points to the base address of the page-directory-pointer table. EPSS estimates a 0.24% chance of exploitation in the next 30 days.

Description

In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits 4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't enforce 32-byte alignment of nCR3. In the absolute worst case scenario, failure to ignore bits 4:0 can result in an out-of-bounds read, e.g. if the target page is at the end of a memslot, and the VMM isn't using guard pages. Per the APM: The CR3 register points to the base address of the page-directory-pointer table. The page-directory-pointer table is aligned on a 32-byte boundary, with the low 5 address bits 4:0 assumed to be 0. And the SDM's much more explicit: 4:0 Ignored Note, KVM gets this right when loading PDPTRs, it's only the nSVM flow that is broken.

Metrics

CVSS 3.1
7.1/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS Probability
0.24%

15.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersionsUpdate
LinuxLinux Kernel>= 3.2, < 5.10.229—
LinuxLinux Kernel>= 5.11, < 5.15.170—
LinuxLinux Kernel>= 5.16, < 6.1.115—
LinuxLinux Kernel>= 6.2, < 6.6.59—
LinuxLinux Kernel>= 6.7, < 6.11.6—
LinuxLinux Kernel6.12Rc1

References

Timeline

Published
Last Modified
Status
Modified

Frequently Asked Questions

What is CVE-2024-50115?
In the Linux kernel, the following vulnerability has been resolved: KVM: nSVM: Ignore nCR3[4:0] when loading PDPTEs from memory Ignore nCR3[4:0] when loading PDPTEs from memory for nested SVM, as bits 4:0 of CR3 are ignored when PAE paging is used, and thus VMRUN doesn't enforce 32-byte alignment of nCR3. In the absolute worst case scenario, failure to ignore bits 4:0 can result in an out-of-bounds read, e.g. if the target page is at the end of a memslot, and the VMM isn't using guard pages. Per the APM: The CR3 register points to the base address of the page-directory-pointer table. The page-directory-pointer table is aligned on a 32-byte boundary, with the low 5 address bits 4:0 assumed to be 0. And the SDM's much more explicit: 4:0 Ignored Note, KVM gets this right when loading PDPTRs, it's only the nSVM flow that is broken.
How severe is CVE-2024-50115?
CVE-2024-50115 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.24% probability of exploitation in the next 30 days.
How do I fix CVE-2024-50115?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-50115?

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Source: NVD / NIST