CVE-2026-80724

In the Linux kernel, the following vulnerability has been resolved: ptp: vmclock: prevent read-only mappings from becoming writable vmclock_miscdev_mmap() rejects writable mappings of the shared vmclock ABI page with -EROFS, but leaves VM_MAYWRITE set. Userspace can map the page read-only and then upgrade it to writable with mprotect(), after which the guest can corrupt the host-written timekeeping data (sequence counter, UTC time, TSC offset) that the vmclock ABI defines as read-only. Clear VM_MAYWRITE on the read-only path so the mapping cannot be upgraded, as i915 does for its read-only objects and as fixed in drm/vc4 (CVE-2026-68445) and drm/panthor (CVE-2024-53071).

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.0 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://git.kernel.org/stable/c/0ce59c4148ecd1520c5592a63bb3c8991ee2d326
https://git.kernel.org/stable/c/2496e141827102d6af512950057d402a2cfb2bfc
https://git.kernel.org/stable/c/2e596e7814ba38cdc129991058b6c254ed37cb11
https://git.kernel.org/stable/c/3f5677d2f817355147337f0453174c7bb0f3b66a
https://git.kernel.org/stable/c/5b4f2bec7bea6c04084d720d731bedee7caf878d
https://git.kernel.org/stable/c/a5edadbae57e2298a56cf7a4e774a027905a331f

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 08:16

Updated : 2026-09-07 16:17

NVD link : CVE-2026-80724

Mitre link : CVE-2026-80724

CVE.ORG link : CVE-2026-80724

JSON object : View

Products Affected

No product.

CWE

No CWE.

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