{"api_version":"1","generated_at":"2026-09-11T22:05:30+00:00","cve":"CVE-2026-89685","urls":{"html":"https://cve.report/CVE-2026-89685","api":"https://cve.report/api/cve/CVE-2026-89685.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-89685","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-89685"},"summary":{"title":"nfsd: fix clock domain mismatch in clients_still_reclaiming()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix clock domain mismatch in clients_still_reclaiming()\n\nclients_still_reclaiming() computes a deadline from nn->boot_time\n(CLOCK_REALTIME, ~1.7 billion) but compares it against\nktime_get_boottime_seconds() (CLOCK_BOOTTIME, seconds since boot).\nThe comparison is always false — it would take ~54 years of uptime\nfor BOOTTIME to exceed the REALTIME-derived deadline.\n\nThis means any client can hold the server in grace indefinitely by\nsending CLAIM_PREVIOUS OPEN requests, blocking all non-reclaim\noperations for all other clients.\n\nAdd boot_time_bt (CLOCK_BOOTTIME) alongside the existing boot_time\nand use it for the deadline computation. boot_time (CLOCK_REALTIME)\nis preserved for its cl_boot clientid-nonce role.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-11 20:19:55","updated_at":"2026-09-11 20:19:55"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/f9cec313efb2fd18d962aad738a4892bce806016","name":"https://git.kernel.org/stable/c/f9cec313efb2fd18d962aad738a4892bce806016","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/9843649196221152b6e5d138a3ce859bdaae1d96","name":"https://git.kernel.org/stable/c/9843649196221152b6e5d138a3ce859bdaae1d96","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/09ea3eb9a518565f5bca386e81b993ed8825f5e8","name":"https://git.kernel.org/stable/c/09ea3eb9a518565f5bca386e81b993ed8825f5e8","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-89685","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-89685","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf f9cec313efb2fd18d962aad738a4892bce806016 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf 9843649196221152b6e5d138a3ce859bdaae1d96 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 20b7d86f29d39e8ae19bb29c24ffee70dc385ddf 09ea3eb9a518565f5bca386e81b993ed8825f5e8 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.6","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.6 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.51 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2.4 7.2.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.3-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["fs/nfsd/netns.h","fs/nfsd/nfs4state.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"f9cec313efb2fd18d962aad738a4892bce806016","status":"affected","version":"20b7d86f29d39e8ae19bb29c24ffee70dc385ddf","versionType":"git"},{"lessThan":"9843649196221152b6e5d138a3ce859bdaae1d96","status":"affected","version":"20b7d86f29d39e8ae19bb29c24ffee70dc385ddf","versionType":"git"},{"lessThan":"09ea3eb9a518565f5bca386e81b993ed8825f5e8","status":"affected","version":"20b7d86f29d39e8ae19bb29c24ffee70dc385ddf","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["fs/nfsd/netns.h","fs/nfsd/nfs4state.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.6"},{"lessThan":"5.6","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.51","versionType":"semver"},{"lessThanOrEqual":"7.2.*","status":"unaffected","version":"7.2.4","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.3-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.51","versionStartIncluding":"5.6","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2.4","versionStartIncluding":"5.6","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.3-rc1","versionStartIncluding":"5.6","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix clock domain mismatch in clients_still_reclaiming()\n\nclients_still_reclaiming() computes a deadline from nn->boot_time\n(CLOCK_REALTIME, ~1.7 billion) but compares it against\nktime_get_boottime_seconds() (CLOCK_BOOTTIME, seconds since boot).\nThe comparison is always false — it would take ~54 years of uptime\nfor BOOTTIME to exceed the REALTIME-derived deadline.\n\nThis means any client can hold the server in grace indefinitely by\nsending CLAIM_PREVIOUS OPEN requests, blocking all non-reclaim\noperations for all other clients.\n\nAdd boot_time_bt (CLOCK_BOOTTIME) alongside the existing boot_time\nand use it for the deadline computation. boot_time (CLOCK_REALTIME)\nis preserved for its cl_boot clientid-nonce role."}],"providerMetadata":{"dateUpdated":"2026-09-11T19:46:07.116Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f9cec313efb2fd18d962aad738a4892bce806016"},{"url":"https://git.kernel.org/stable/c/9843649196221152b6e5d138a3ce859bdaae1d96"},{"url":"https://git.kernel.org/stable/c/09ea3eb9a518565f5bca386e81b993ed8825f5e8"}],"title":"nfsd: fix clock domain mismatch in clients_still_reclaiming()","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-89685","datePublished":"2026-09-11T19:46:07.116Z","dateReserved":"2026-09-11T19:38:34.749Z","dateUpdated":"2026-09-11T19:46:07.116Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-11 20:19:55","lastModifiedDate":"2026-09-11 20:19:55","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"89685","Ordinal":"1","Title":"nfsd: fix clock domain mismatch in clients_still_reclaiming()","CVE":"CVE-2026-89685","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"89685","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfsd: fix clock domain mismatch in clients_still_reclaiming()\n\nclients_still_reclaiming() computes a deadline from nn->boot_time\n(CLOCK_REALTIME, ~1.7 billion) but compares it against\nktime_get_boottime_seconds() (CLOCK_BOOTTIME, seconds since boot).\nThe comparison is always false — it would take ~54 years of uptime\nfor BOOTTIME to exceed the REALTIME-derived deadline.\n\nThis means any client can hold the server in grace indefinitely by\nsending CLAIM_PREVIOUS OPEN requests, blocking all non-reclaim\noperations for all other clients.\n\nAdd boot_time_bt (CLOCK_BOOTTIME) alongside the existing boot_time\nand use it for the deadline computation. boot_time (CLOCK_REALTIME)\nis preserved for its cl_boot clientid-nonce role.","Type":"Description","Title":"nfsd: fix clock domain mismatch in clients_still_reclaiming()"}]}}}