{"id":"CVE-2026-63977","state":"PUBLISHED","title":"dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work","description":"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.","publishedAt":"2026-07-19T14:56:01.889Z","updatedAt":"2026-10-19T20:18:00.021Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9363b4837659d1b7ee04cfa714373ce4b4b8269f","status":"affected","lessThan":"e7a33807fb3f87a855993474ac21684ce105927b","versionType":"git"},{"version":"9363b4837659d1b7ee04cfa714373ce4b4b8269f","status":"affected","lessThan":"d733f519f6443540f8359461a34e3b0042099bbe","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dpll/zl3073x/dpll.c","drivers/dpll/zl3073x/dpll.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dpll/zl3073x/dpll.c","drivers/dpll/zl3073x/dpll.h"]}],"references":["https://git.kernel.org/stable/c/e7a33807fb3f87a855993474ac21684ce105927b","https://git.kernel.org/stable/c/d733f519f6443540f8359461a34e3b0042099bbe"],"weaknesses":["CWE-362"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63977.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63977","state":"PUBLISHED","datePublished":"2026-07-19T14:56:01.889Z","dateUpdated":"2026-10-19T20:18:00.021Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-07-19T07:54:57.024Z"},"containers":{"cna":{"title":"dpll: zl3073x: use __dpll_device_change_ntf() and remove change_work","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."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"9363b4837659d1b7ee04cfa714373ce4b4b8269f","status":"affected","lessThan":"e7a33807fb3f87a855993474ac21684ce105927b","versionType":"git"},{"version":"9363b4837659d1b7ee04cfa714373ce4b4b8269f","status":"affected","lessThan":"d733f519f6443540f8359461a34e3b0042099bbe","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dpll/zl3073x/dpll.c","drivers/dpll/zl3073x/dpll.h"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.18","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.18","versionType":"semver"},{"version":"7.0.12","status":"unaffected","lessThanOrEqual":"7.0.*","versionType":"semver"},{"version":"7.1","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/dpll/zl3073x/dpll.c","drivers/dpll/zl3073x/dpll.h"]}],"references":[{"url":"https://git.kernel.org/stable/c/e7a33807fb3f87a855993474ac21684ce105927b"},{"url":"https://git.kernel.org/stable/c/d733f519f6443540f8359461a34e3b0042099bbe"}],"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."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:37:48.157Z"},"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"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-63977","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"version":"2.0.3","timestamp":"2026-10-16T15:34:28.879643Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-362","lang":"en","type":"CWE","description":"CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T20:18:00.021Z"}}]}}}