{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63977",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.024Z",
        "datePublished": "2026-07-19T14:56:01.889Z",
        "dateUpdated": "2026-08-05T12:37:48.157Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:37:48.157Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ndpll: zl3073x: use __dpll_device_change_ntf() and remove change_work\n\nThe change_work was introduced to send device change notifications\nfrom DPLL device callbacks without deadlocking on dpll_lock, since\nthe callbacks are already invoked under that lock. Now that\n__dpll_device_change_ntf() is exported for callers that already\nhold dpll_lock, use it directly and remove the change_work\ninfrastructure entirely.\n\nThis eliminates a race condition where change_work could be\nre-scheduled after cancel_work_sync() during device teardown,\npotentially causing the handler to dereference a freed or NULL\ndpll_dev pointer."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The bug is reached only through the DPLL generic-netlink interface (`DPLL_CMD_DEVICE_SET` with `DPLL_A_PHASE_OFFSET_AVG_FACTOR`), which requires a local `sendmsg()`/netlink syscall. The zl3073x driver is an on-board I2C/SPI timing chip driver and is not exposed via remote network packet handling.\nAC:L - Exploitation is a use-after-free race where the attacker controls the scheduling side by repeatedly issuing concurrent DPLL netlink SET requests (`parallel_ops` is enabled). The teardown window is created during sibling-DPLL unregistration in `zl3073x_dev_stop()`, which occurs on driver remove/reboot/maintenance that the attacker can time against.\nPR:L - All DPLL netlink operations are gated by `GENL_ADMIN_PERM`, which requires `CAP_NET_ADMIN`. That capability is obtainable by an unprivileged user via user namespaces (`unshare -Urn`), and the DPLL family is `netnsok`, so this is not restricted to real init-namespace root.\nUI:N - Triggering the race requires only automated netlink traffic from the attacker; no victim user action such as opening a file or mounting a filesystem is needed.\nS:U - Impact is kernel memory corruption and potential privilege escalation within the same kernel security authority. This is not a VM/guest escape or IOMMU boundary bypass.\nC:H - The race leaves a deferred work item that calls `dpll_device_change_ntf()` on a `dpll_dev` pointer that may already be freed, causing a classic use-after-free with reads of freed `struct dpll_device` fields (`id`, `clock_id`, `type`, etc.).\nI:H - Use-after-free of a heap-allocated `struct dpll_device` can be leveraged for controlled reuse and arbitrary kernel memory corruption, including potential control-flow hijacking, not merely a benign crash.\nA:H - Dereferencing a freed or NULL `dpll_dev` from the workqueue handler can cause a kernel oops/panic during device teardown, and UAF conditions inherently threaten system availability even when full exploitation is not attempted."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/dpll/zl3073x/dpll.c",
                        "drivers/dpll/zl3073x/dpll.h"
                    ],
                    "versions": [
                        {
                            "version": "9363b4837659d1b7ee04cfa714373ce4b4b8269f",
                            "lessThan": "e7a33807fb3f87a855993474ac21684ce105927b",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "9363b4837659d1b7ee04cfa714373ce4b4b8269f",
                            "lessThan": "d733f519f6443540f8359461a34e3b0042099bbe",
                            "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/dpll/zl3073x/dpll.c",
                        "drivers/dpll/zl3073x/dpll.h"
                    ],
                    "versions": [
                        {
                            "version": "6.18",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.18",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.12",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.18",
                                    "versionEndExcluding": "7.0.12"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.18",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/e7a33807fb3f87a855993474ac21684ce105927b"
                },
                {
                    "url": "https://git.kernel.org/stable/c/d733f519f6443540f8359461a34e3b0042099bbe"
                }
            ],
            "title": "dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}