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.
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.
Published:
2026-01-05
Score:
n/a
EPSS:
< 1% Very Low
KEV:
No
Impact:
n/a
Action:
n/a
Analysis and contextual insights are available on OpenCVE Cloud.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
Sign in to view the affected projects.
Advisories
| Source | ID | Title |
|---|---|---|
Ubuntu USN |
USN-8094-1 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-8094-2 | Linux kernel vulnerabilities |
Ubuntu USN |
USN-8094-3 | Linux kernel (Real-time) vulnerabilities |
Ubuntu USN |
USN-8094-4 | Linux kernel (Azure) vulnerabilities |
Ubuntu USN |
USN-8094-5 | Linux kernel (Raspberry Pi) vulnerabilities |
Ubuntu USN |
USN-8152-1 | Linux kernel (OEM) vulnerabilities |
References
History
Tue, 06 Jan 2026 00:15:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| References |
|
Mon, 05 Jan 2026 10:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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. | |
| Title | iommu/amd: Fix potential out-of-bounds read in iommu_mmio_show | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-05-11T21:52:49.261Z
Reserved: 2025-12-24T10:30:51.033Z
Link: CVE-2025-68760
No data.
Status : Deferred
Published: 2026-01-05T10:15:57.123
Modified: 2026-04-15T00:35:42.020
Link: CVE-2025-68760
OpenCVE Enrichment
No data.
Weaknesses
No weakness.
Ubuntu USN