CVE-2025-68760
Awaiting Analysis Awaiting Analysis - Queue
BaseFortify

Publication date: 2026-01-05

Last updated on: 2026-01-08

Assigner: kernel.org

Description
In the Linux kernel, the following vulnerability has been resolved: iommu/amd: Fix potential out-of-bounds read in iommu_mmio_show In iommu_mmio_write(), it validates the user-provided offset with the check: `iommu->dbg_mmio_offset > iommu->mmio_phys_end - 4`. This assumes a 4-byte access. However, the corresponding show handler, iommu_mmio_show(), uses readq() to perform an 8-byte (64-bit) read. If a user provides an offset equal to `mmio_phys_end - 4`, the check passes, and will lead to a 4-byte out-of-bounds read. Fix this by adjusting the boundary check to use sizeof(u64), which corresponds to the size of the readq() operation.
CVSS Scores
EPSS Scores
Probability:
Percentile:
Meta Information
Published
2026-01-05
Last Modified
2026-01-08
Generated
2026-05-07
AI Q&A
2026-01-05
EPSS Evaluated
2026-05-05
NVD
EUVD
Affected Vendors & Products
Showing 1 associated CPE
Vendor Product Version / Range
linux linux_kernel *
Helpful Resources
Exploitability
CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?

This vulnerability is a potential out-of-bounds read in the Linux kernel's iommu/amd component. Specifically, the function iommu_mmio_write() validates a user-provided offset assuming a 4-byte access, but the corresponding iommu_mmio_show() function performs an 8-byte read. If a user provides an offset at the boundary (mmio_phys_end - 4), the check passes incorrectly, leading to a 4-byte out-of-bounds read. The fix involved adjusting the boundary check to match the 8-byte read size.


How can this vulnerability impact me? :

This vulnerability can lead to an out-of-bounds read in kernel memory, which may cause information disclosure or system instability. An attacker could potentially exploit this to read unintended memory areas, possibly leaking sensitive information or causing a denial of service.


What immediate steps should I take to mitigate this vulnerability?

To mitigate this vulnerability, update the Linux kernel to a version that includes the fix for the iommu/amd out-of-bounds read issue. The fix involves adjusting the boundary check in iommu_mmio_write() to correctly handle 8-byte reads, preventing out-of-bounds access. Until the update is applied, restrict untrusted user access to the affected iommu interfaces to minimize risk.


Ask Our AI Assistant
Need more information? Ask your question to get an AI reply (Powered by our expertise)
0/70
EPSS Chart