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 3.1

8.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

EPSS

0.2% chance of exploitation in the next 30 days; higher than 7% of CVEs (scores of 2026-10-25)

Published

2026-08-28

Modified

2026-10-19

Record from

the NVD, synced 2026-10-19

References

• 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

Check your stackJSON