{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2025-68250", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-12-16T13:41:40.266Z", "datePublished": "2025-12-16T14:32:17.173Z", "dateUpdated": "2026-08-05T12:10:27.999Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:10:27.999Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nhung_task: fix warnings caused by unaligned lock pointers\n\nThe blocker tracking mechanism assumes that lock pointers are at least\n4-byte aligned to use their lower bits for type encoding.\n\nHowever, as reported by Eero Tamminen, some architectures like m68k\nonly guarantee 2-byte alignment of 32-bit values. This breaks the\nassumption and causes two related WARN_ON_ONCE checks to trigger.\n\nTo fix this, the runtime checks are adjusted to silently ignore any lock\nthat is not 4-byte aligned, effectively disabling the feature in such\ncases and avoiding the related warnings.\n\nThanks to Geert Uytterhoeven for bisecting!" } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H", "baseScore": 8.2, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:N - On an affected m68k system running ksmbd, remote SMB2 IPC-pipe requests can contend on the unaligned session RPC rwsem and reach the vulnerable blocker tracking code over TCP/445.\nAC:L - The client can deterministically trigger the contemporaneous recursive-lock path or control concurrent requests against one session, so exploitation requires no uncontrollable race or memory-layout manipulation.\nPR:N - KSMBD permits passwordless guest sessions and allows restricted guest RPC operations, making the path reachable without credentials in a reasonable guest-enabled deployment.\nUI:N - Once the service is configured, attacker-supplied SMB requests trigger the vulnerable path without victim action.\nS:U - The warning, information exposure, and possible panic affect the same kernel and host security authority as the vulnerable code.\nC:L - The warning dumps kernel addresses and up to 48 raw m68k stack words, providing a bounded information disclosure where the kernel log or console is accessible.\nI:N - The rejected unaligned pointer is never stored or dereferenced, and the bug causes no memory corruption or attacker-controlled data modification.\nA:H - The warning immediately panics the kernel when panic_on_warn is enabled or the warning limit is reached, causing complete host unavailability." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/hung_task.h" ], "versions": [ { "version": "e711faaafbe54a884f33b53472434063d342f6d4", "lessThan": "c0e2dcbe54cb15ecdf9d8f4501c6720423243888", "status": "affected", "versionType": "git" }, { "version": "e711faaafbe54a884f33b53472434063d342f6d4", "lessThan": "c97513cddcfc235f2522617980838e500af21d01", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/linux/hung_task.h" ], "versions": [ { "version": "6.16", "status": "affected" }, { "version": "0", "lessThan": "6.16", "status": "unaffected", "versionType": "semver" }, { "version": "6.17.6", "lessThanOrEqual": "6.17.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18", "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": "6.16", "versionEndExcluding": "6.17.6" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.16", "versionEndExcluding": "6.18" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/c0e2dcbe54cb15ecdf9d8f4501c6720423243888" }, { "url": "https://git.kernel.org/stable/c/c97513cddcfc235f2522617980838e500af21d01" } ], "title": "hung_task: fix warnings caused by unaligned lock pointers", "x_generator": { "engine": "bippy-1.2.0" } } } }