ptp: vmclock: prevent read-only mappings from becoming writable
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).
CVE-2026-80724
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-80724
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "5b4f2bec7bea6c04084d720d731bedee7caf878d",
"versionType": "git"
},
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "3f5677d2f817355147337f0453174c7bb0f3b66a",
"versionType": "git"
},
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "2496e141827102d6af512950057d402a2cfb2bfc",
"versionType": "git"
},
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "2e596e7814ba38cdc129991058b6c254ed37cb11",
"versionType": "git"
},
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "0ce59c4148ecd1520c5592a63bb3c8991ee2d326",
"versionType": "git"
},
{
"status": "affected",
"version": "20503272422693d793b84f88bf23fe4e955d3a33",
"lessThan": "a5edadbae57e2298a56cf7a4e774a027905a331f",
"versionType": "git"
}
],
"programFiles": [
"drivers/ptp/ptp_vmclock.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "6.13"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "6.13",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.18.47",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.18.50",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.11",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2.1",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.2.4",
"versionType": "semver",
"lessThanOrEqual": "7.2.*"
},
{
"status": "unaffected",
"version": "7.3",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"drivers/ptp/ptp_vmclock.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-80724
Source reference:
/cveMetadata/cveId
Publisher severity
high
Source reference: /containers/cna/metrics
- Event
- #34777 · Revision 1
- Added to Heist Feed
- Publisher date