{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-68134",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-30T09:28:09.370Z",
        "datePublished": "2026-08-10T11:58:57.504Z",
        "dateUpdated": "2026-08-17T04:59:26.371Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T04:59:26.371Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nptp: ptp_s390: Add missing facility check\n\nOnly register the physical clock when facility 28 is installed\nand PTFF QAF returns that PTFF QPT is available."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H",
                        "baseScore": 7.3,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The bug is reached only via local PTP character-device access: open(/dev/ptpX) followed by ioctl paths such as PTP_SYS_OFFSET or clock_gettime on the posix clock FD, which call ptp_s390_qpt_gettime() and execute the PTFF instruction in kernel context.\nAC:L - On affected IBM Z systems with the s390 PTP driver enabled, any process that can open the physical-clock device can repeatedly issue read ioctls that deterministically invoke PTFF without races or attacker-uncontrollable timing.\nPR:L - PTP read ioctls and clock_gettime do not require CAP_SYS_TIME; on typical chrony/ptp4l and containerized time-sync deployments /dev/ptp* is often opened by non-root service accounts or passed into unprivileged workloads, not only init-namespace root.\nUI:N - Exploitation requires only the attacker (or their service account) opening the PTP device and issuing ioctls; no separate victim action such as mounting a filesystem or clicking a prompt is needed.\nS:U - Impact is confined to the same Linux kernel running the ptp_s390 driver on the s390 host; it does not cross a VM, IOMMU, or other security boundary to another authority.\nC:H - When PTFF QPT is unavailable the driver still calls ptff() and returns the unchecked stack buffer to userspace, leaking kernel memory; on systems without facility 28 the illegal PTFF traps in kernel mode and can expose register/state data during the fault path.\nI:L - Returning attacker-influenced or uninitialized PTFF output as authoritative PTP time via ioctl can corrupt time-sync decisions for chrony/ptp4l and other consumers that steer system clocks from the physical-clock device.\nA:H - Executing PTFF without facility 28 or on unsupported configurations triggers an s390 program check in kernel context (illegal/specification exception) that ends in die(), causing a kernel oops/panic and total loss of host availability."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/ptp/ptp_s390.c"
                    ],
                    "versions": [
                        {
                            "version": "2d7de7a3010d713fb89b7ba99e6fdc14475ad106",
                            "lessThan": "b3efb4744abf493c9782eae713b861a80d9bbeca",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2d7de7a3010d713fb89b7ba99e6fdc14475ad106",
                            "lessThan": "545a7fdbc110c82933d448db2695abff07536f08",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "2d7de7a3010d713fb89b7ba99e6fdc14475ad106",
                            "lessThan": "e78f1ac37afcb16cb6fef8a2c92591eab6558956",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/ptp/ptp_s390.c"
                    ],
                    "versions": [
                        {
                            "version": "6.13",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.13",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.42",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.6",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
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                            "operator": "OR",
                            "negate": false,
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                                    "versionEndExcluding": "6.18.42"
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                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.13",
                                    "versionEndExcluding": "7.1.6"
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                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.13",
                                    "versionEndExcluding": "7.2"
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/b3efb4744abf493c9782eae713b861a80d9bbeca"
                },
                {
                    "url": "https://git.kernel.org/stable/c/545a7fdbc110c82933d448db2695abff07536f08"
                },
                {
                    "url": "https://git.kernel.org/stable/c/e78f1ac37afcb16cb6fef8a2c92591eab6558956"
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            ],
            "title": "ptp: ptp_s390: Add missing facility check",
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