Vulnerability-Lookup

CVE-2026-64437 (GCVE-0-2026-64437)

Vulnerability from cvelistv5 – Published: 2026-07-25 08:51 – Updated: 2026-07-25 08:51

Title

ksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL

Summary

In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL Commit f580d27e8928 ("ksmbd: fix use-after-free of a deferred file_lock on double SMB2_CANCEL") made smb2_cancel() skip a work whose state is KSMBD_WORK_CANCELLED, so its cancel_fn cannot be fired a second time. But KSMBD_WORK has three states (ACTIVE, CANCELLED, CLOSED), and the same freeing producer path is reached for CLOSED too: SMB2_CLOSE on the locking handle -> set_close_state_blocked_works() sets the deferred work's state to KSMBD_WORK_CLOSED and wakes the smb2_lock() worker. The worker takes the non-ACTIVE early-exit, locks_free_lock()s the file_lock and, because the state is not KSMBD_WORK_CANCELLED, takes the STATUS_RANGE_NOT_LOCKED branch with "goto out2" -- which, like the cancelled branch, skips release_async_work(). The work stays on conn->async_requests with a live cancel_fn = smb2_remove_blocked_lock pointing at the freed file_lock. A subsequent SMB2_CANCEL for the same AsyncId then passes the KSMBD_WORK_CANCELLED-only guard (its state is KSMBD_WORK_CLOSED), so smb2_cancel() fires cancel_fn again over the freed file_lock -- the same use-after-free fixed, via SMB2_CLOSE instead of a first SMB2_CANCEL: BUG: KASAN: slab-use-after-free in __locks_delete_block __locks_delete_block locks_delete_block ksmbd_vfs_posix_lock_unblock smb2_remove_blocked_lock smb2_cancel <- 2nd SMB2_CANCEL fires cancel_fn handle_ksmbd_work Allocated by ...: locks_alloc_lock <- smb2_lock Freed by ...: locks_free_lock <- smb2_lock (non-ACTIVE early-exit) ... cache file_lock_cache of size 192 Reproduced on mainline 7.1-rc7 (which already contains f580d27e8928) with KASAN by an authenticated SMB client; the double-SMB2_CANCEL control is silent on that kernel, so the splat is attributable to the CLOSE trigger. Only an ACTIVE deferred work may have its cancel_fn fired: both terminal states (CANCELLED and CLOSED) reach the smb2_lock() early-exit that frees the file_lock and skips release_async_work(). Guard on KSMBD_WORK_ACTIVE so any non-active work is skipped.

Severity

No CVSS data available.

Assigner

Linux

References

6 references

URL	Tags
https://git.kernel.org/stable/c/a796ba4e61d5e14e0…
https://git.kernel.org/stable/c/b8e274e69ab09222c…
https://git.kernel.org/stable/c/ddb9239828336b36d…
https://git.kernel.org/stable/c/94083db751930b154…
https://git.kernel.org/stable/c/12c36c99655f325be…
https://git.kernel.org/stable/c/10f293a07f9e10e98…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: b7063c7426ea5a4d15e01b60538718765392f49d , < a796ba4e61d5e14e07b79a359faac69f8f9b22a3 (git) Affected: 0da2e073f9cbf4985a0fd9acb71bc5ff599f8afd , < b8e274e69ab09222c7a552c7c0c1eef9ce627fc1 (git) Affected: 89ae9df09d2c1fb4a4eb495c113a7ce1dca34147 , < ddb9239828336b36d8a3ef5943fdffb2f55b6508 (git) Affected: 14d2eee0193ac3cd1bf3d014373449f0b8d35d6d , < 94083db751930b1540ddff2b54d4677549c57f81 (git) Affected: f580d27e8928828693df44ba2db0fffdbe11dfea , < 12c36c99655f325befe50c26842f7deca414c381 (git) Affected: f580d27e8928828693df44ba2db0fffdbe11dfea , < 10f293a07f9e10e988b0ae44e2e99c631f5a68e0 (git) Affected: 2b2eda2821cff1d1b5a423b6ee7d8fc6fbc8e694 (git) Affected: 6.1.176 , < 6.1.178 (semver) Affected: 6.6.143 , < 6.6.145 (semver) Affected: 6.12.94 , < 6.12.96 (semver) Affected: 6.18.36 , < 6.18.39 (semver) Affected: 7.0.13 , < 7.1 (semver)
Linux	Linux	Affected: 7.1 Unaffected: 0 , < 7.1 (semver) Unaffected: 6.1.178 , ≤ 6.1.* (semver) Unaffected: 6.6.145 , ≤ 6.6.* (semver) Unaffected: 6.12.96 , ≤ 6.12.* (semver) Unaffected: 6.18.39 , ≤ 6.18.* (semver) Unaffected: 7.1.4 , ≤ 7.1.* (semver) Unaffected: 7.2-rc1 , ≤ * (original_commit_for_fix)

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              "status": "unaffected",
              "version": "6.12.96",
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              "lessThanOrEqual": "6.18.*",
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          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL\n\nCommit f580d27e8928 (\"ksmbd: fix use-after-free of a deferred file_lock on\ndouble SMB2_CANCEL\") made smb2_cancel() skip a work whose state is\nKSMBD_WORK_CANCELLED, so its cancel_fn cannot be fired a second time. But\nKSMBD_WORK has three states (ACTIVE, CANCELLED, CLOSED), and the same\nfreeing producer path is reached for CLOSED too:\n\n  SMB2_CLOSE on the locking handle -\u003e set_close_state_blocked_works() sets\n  the deferred work\u0027s state to KSMBD_WORK_CLOSED and wakes the smb2_lock()\n  worker. The worker takes the non-ACTIVE early-exit, locks_free_lock()s\n  the file_lock and, because the state is not KSMBD_WORK_CANCELLED, takes\n  the STATUS_RANGE_NOT_LOCKED branch with \"goto out2\" -- which, like the\n  cancelled branch, skips release_async_work(). The work stays on\n  conn-\u003easync_requests with a live cancel_fn = smb2_remove_blocked_lock\n  pointing at the freed file_lock.\n\nA subsequent SMB2_CANCEL for the same AsyncId then passes the\nKSMBD_WORK_CANCELLED-only guard (its state is KSMBD_WORK_CLOSED), so\nsmb2_cancel() fires cancel_fn again over the freed file_lock -- the same\nuse-after-free fixed, via SMB2_CLOSE instead of a first SMB2_CANCEL:\n\n  BUG: KASAN: slab-use-after-free in __locks_delete_block\n    __locks_delete_block\n    locks_delete_block\n    ksmbd_vfs_posix_lock_unblock\n    smb2_remove_blocked_lock\n    smb2_cancel                 \u003c- 2nd SMB2_CANCEL fires cancel_fn\n    handle_ksmbd_work\n  Allocated by ...: locks_alloc_lock \u003c- smb2_lock\n  Freed by ...:     locks_free_lock  \u003c- smb2_lock (non-ACTIVE early-exit)\n  ... cache file_lock_cache of size 192\n\nReproduced on mainline 7.1-rc7 (which already contains f580d27e8928) with\nKASAN by an authenticated SMB client; the double-SMB2_CANCEL control is\nsilent on that kernel, so the splat is attributable to the CLOSE trigger.\n\nOnly an ACTIVE deferred work may have its cancel_fn fired: both terminal\nstates (CANCELLED and CLOSED) reach the smb2_lock() early-exit that frees\nthe file_lock and skips release_async_work(). Guard on KSMBD_WORK_ACTIVE\nso any non-active work is skipped."
        }
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        "dateUpdated": "2026-07-25T08:51:11.072Z",
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        "shortName": "Linux"
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          "url": "https://git.kernel.org/stable/c/a796ba4e61d5e14e07b79a359faac69f8f9b22a3"
        },
        {
          "url": "https://git.kernel.org/stable/c/b8e274e69ab09222c7a552c7c0c1eef9ce627fc1"
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          "url": "https://git.kernel.org/stable/c/94083db751930b1540ddff2b54d4677549c57f81"
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          "url": "https://git.kernel.org/stable/c/10f293a07f9e10e988b0ae44e2e99c631f5a68e0"
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      "title": "ksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL",
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    "cveId": "CVE-2026-64437",
    "datePublished": "2026-07-25T08:51:11.072Z",
    "dateReserved": "2026-07-19T15:36:31.788Z",
    "dateUpdated": "2026-07-25T08:51:11.072Z",
    "state": "PUBLISHED"
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    "epss": {
      "cve": "CVE-2026-64437",
      "date": "2026-07-26",
      "epss": "0.00173",
      "percentile": "0.06924"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-64437\",\"sourceIdentifier\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"published\":\"2026-07-25T10:17:28.160\",\"lastModified\":\"2026-07-25T10:17:28.160\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"In the Linux kernel, the following vulnerability has been resolved:\\n\\nksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL\\n\\nCommit f580d27e8928 (\\\"ksmbd: fix use-after-free of a deferred file_lock on\\ndouble SMB2_CANCEL\\\") made smb2_cancel() skip a work whose state is\\nKSMBD_WORK_CANCELLED, so its cancel_fn cannot be fired a second time. But\\nKSMBD_WORK has three states (ACTIVE, CANCELLED, CLOSED), and the same\\nfreeing producer path is reached for CLOSED too:\\n\\n  SMB2_CLOSE on the locking handle -\u003e set_close_state_blocked_works() sets\\n  the deferred work\u0027s state to KSMBD_WORK_CLOSED and wakes the smb2_lock()\\n  worker. The worker takes the non-ACTIVE early-exit, locks_free_lock()s\\n  the file_lock and, because the state is not KSMBD_WORK_CANCELLED, takes\\n  the STATUS_RANGE_NOT_LOCKED branch with \\\"goto out2\\\" -- which, like the\\n  cancelled branch, skips release_async_work(). The work stays on\\n  conn-\u003easync_requests with a live cancel_fn = smb2_remove_blocked_lock\\n  pointing at the freed file_lock.\\n\\nA subsequent SMB2_CANCEL for the same AsyncId then passes the\\nKSMBD_WORK_CANCELLED-only guard (its state is KSMBD_WORK_CLOSED), so\\nsmb2_cancel() fires cancel_fn again over the freed file_lock -- the same\\nuse-after-free fixed, via SMB2_CLOSE instead of a first SMB2_CANCEL:\\n\\n  BUG: KASAN: slab-use-after-free in __locks_delete_block\\n    __locks_delete_block\\n    locks_delete_block\\n    ksmbd_vfs_posix_lock_unblock\\n    smb2_remove_blocked_lock\\n    smb2_cancel                 \u003c- 2nd SMB2_CANCEL fires cancel_fn\\n    handle_ksmbd_work\\n  Allocated by ...: locks_alloc_lock \u003c- smb2_lock\\n  Freed by ...:     locks_free_lock  \u003c- smb2_lock (non-ACTIVE early-exit)\\n  ... cache file_lock_cache of size 192\\n\\nReproduced on mainline 7.1-rc7 (which already contains f580d27e8928) with\\nKASAN by an authenticated SMB client; the double-SMB2_CANCEL control is\\nsilent on that kernel, so the splat is attributable to the CLOSE trigger.\\n\\nOnly an ACTIVE deferred work may have its cancel_fn fired: both terminal\\nstates (CANCELLED and CLOSED) reach the smb2_lock() early-exit that frees\\nthe file_lock and skips release_async_work(). Guard on KSMBD_WORK_ACTIVE\\nso any non-active work is skipped.\"}],\"affected\":[{\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\",\"affectedData\":[{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"unaffected\",\"programFiles\":[\"fs/smb/server/smb2pdu.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"b7063c7426ea5a4d15e01b60538718765392f49d\",\"lessThan\":\"a796ba4e61d5e14e07b79a359faac69f8f9b22a3\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"0da2e073f9cbf4985a0fd9acb71bc5ff599f8afd\",\"lessThan\":\"b8e274e69ab09222c7a552c7c0c1eef9ce627fc1\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"89ae9df09d2c1fb4a4eb495c113a7ce1dca34147\",\"lessThan\":\"ddb9239828336b36d8a3ef5943fdffb2f55b6508\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"14d2eee0193ac3cd1bf3d014373449f0b8d35d6d\",\"lessThan\":\"94083db751930b1540ddff2b54d4677549c57f81\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f580d27e8928828693df44ba2db0fffdbe11dfea\",\"lessThan\":\"12c36c99655f325befe50c26842f7deca414c381\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"f580d27e8928828693df44ba2db0fffdbe11dfea\",\"lessThan\":\"10f293a07f9e10e988b0ae44e2e99c631f5a68e0\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"2b2eda2821cff1d1b5a423b6ee7d8fc6fbc8e694\",\"versionType\":\"git\",\"status\":\"affected\"},{\"version\":\"6.1.176\",\"lessThan\":\"6.1.178\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.6.143\",\"lessThan\":\"6.6.145\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.12.94\",\"lessThan\":\"6.12.96\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"6.18.36\",\"lessThan\":\"6.18.39\",\"versionType\":\"semver\",\"status\":\"affected\"},{\"version\":\"7.0.13\",\"lessThan\":\"7.1\",\"versionType\":\"semver\",\"status\":\"affected\"}]},{\"vendor\":\"Linux\",\"product\":\"Linux\",\"defaultStatus\":\"affected\",\"programFiles\":[\"fs/smb/server/smb2pdu.c\"],\"repo\":\"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\"versions\":[{\"version\":\"7.1\",\"status\":\"affected\"},{\"version\":\"0\",\"lessThan\":\"7.1\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.1.178\",\"lessThanOrEqual\":\"6.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.6.145\",\"lessThanOrEqual\":\"6.6.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.12.96\",\"lessThanOrEqual\":\"6.12.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"6.18.39\",\"lessThanOrEqual\":\"6.18.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.1.4\",\"lessThanOrEqual\":\"7.1.*\",\"versionType\":\"semver\",\"status\":\"unaffected\"},{\"version\":\"7.2-rc1\",\"lessThanOrEqual\":\"*\",\"versionType\":\"original_commit_for_fix\",\"status\":\"unaffected\"}]}]}],\"metrics\":{},\"references\":[{\"url\":\"https://git.kernel.org/stable/c/10f293a07f9e10e988b0ae44e2e99c631f5a68e0\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/12c36c99655f325befe50c26842f7deca414c381\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/94083db751930b1540ddff2b54d4677549c57f81\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/a796ba4e61d5e14e07b79a359faac69f8f9b22a3\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/b8e274e69ab09222c7a552c7c0c1eef9ce627fc1\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"},{\"url\":\"https://git.kernel.org/stable/c/ddb9239828336b36d8a3ef5943fdffb2f55b6508\",\"source\":\"416baaa9-dc9f-4396-8d5f-8c081fb06d67\"}]}}",
    "suse_vex": {
      "aggregate_severity": "not set",
      "current_release_date": "2026-07-25T15:59:21Z",
      "cve": "CVE-2026-64437",
      "id": "CVE-2026-64437",
      "initial_release_date": "2026-07-25T15:59:21Z",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64437",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64437.json",
      "version": "2"
    }
  }
}

GHSA-X5P7-HG5V-9P54

Vulnerability from github – Published: 2026-07-25 12:31 – Updated: 2026-07-25 12:31

Details

In the Linux kernel, the following vulnerability has been resolved:

ksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL

Commit f580d27e8928 ("ksmbd: fix use-after-free of a deferred file_lock on double SMB2_CANCEL") made smb2_cancel() skip a work whose state is KSMBD_WORK_CANCELLED, so its cancel_fn cannot be fired a second time. But KSMBD_WORK has three states (ACTIVE, CANCELLED, CLOSED), and the same freeing producer path is reached for CLOSED too:

SMB2_CLOSE on the locking handle -> set_close_state_blocked_works() sets the deferred work's state to KSMBD_WORK_CLOSED and wakes the smb2_lock() worker. The worker takes the non-ACTIVE early-exit, locks_free_lock()s the file_lock and, because the state is not KSMBD_WORK_CANCELLED, takes the STATUS_RANGE_NOT_LOCKED branch with "goto out2" -- which, like the cancelled branch, skips release_async_work(). The work stays on conn->async_requests with a live cancel_fn = smb2_remove_blocked_lock pointing at the freed file_lock.

A subsequent SMB2_CANCEL for the same AsyncId then passes the KSMBD_WORK_CANCELLED-only guard (its state is KSMBD_WORK_CLOSED), so smb2_cancel() fires cancel_fn again over the freed file_lock -- the same use-after-free fixed, via SMB2_CLOSE instead of a first SMB2_CANCEL:

BUG: KASAN: slab-use-after-free in __locks_delete_block __locks_delete_block locks_delete_block ksmbd_vfs_posix_lock_unblock smb2_remove_blocked_lock smb2_cancel <- 2nd SMB2_CANCEL fires cancel_fn handle_ksmbd_work Allocated by ...: locks_alloc_lock <- smb2_lock Freed by ...: locks_free_lock <- smb2_lock (non-ACTIVE early-exit) ... cache file_lock_cache of size 192

Reproduced on mainline 7.1-rc7 (which already contains f580d27e8928) with KASAN by an authenticated SMB client; the double-SMB2_CANCEL control is silent on that kernel, so the splat is attributable to the CLOSE trigger.

Only an ACTIVE deferred work may have its cancel_fn fired: both terminal states (CANCELLED and CLOSED) reach the smb2_lock() early-exit that frees the file_lock and skips release_async_work(). Guard on KSMBD_WORK_ACTIVE so any non-active work is skipped.

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{
  "affected": [],
  "aliases": [
    "CVE-2026-64437"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-25T10:17:28Z",
    "severity": null
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nksmbd: fix use-after-free of a deferred file_lock on SMB2_CLOSE then SMB2_CANCEL\n\nCommit f580d27e8928 (\"ksmbd: fix use-after-free of a deferred file_lock on\ndouble SMB2_CANCEL\") made smb2_cancel() skip a work whose state is\nKSMBD_WORK_CANCELLED, so its cancel_fn cannot be fired a second time. But\nKSMBD_WORK has three states (ACTIVE, CANCELLED, CLOSED), and the same\nfreeing producer path is reached for CLOSED too:\n\n  SMB2_CLOSE on the locking handle -\u003e set_close_state_blocked_works() sets\n  the deferred work\u0027s state to KSMBD_WORK_CLOSED and wakes the smb2_lock()\n  worker. The worker takes the non-ACTIVE early-exit, locks_free_lock()s\n  the file_lock and, because the state is not KSMBD_WORK_CANCELLED, takes\n  the STATUS_RANGE_NOT_LOCKED branch with \"goto out2\" -- which, like the\n  cancelled branch, skips release_async_work(). The work stays on\n  conn-\u003easync_requests with a live cancel_fn = smb2_remove_blocked_lock\n  pointing at the freed file_lock.\n\nA subsequent SMB2_CANCEL for the same AsyncId then passes the\nKSMBD_WORK_CANCELLED-only guard (its state is KSMBD_WORK_CLOSED), so\nsmb2_cancel() fires cancel_fn again over the freed file_lock -- the same\nuse-after-free fixed, via SMB2_CLOSE instead of a first SMB2_CANCEL:\n\n  BUG: KASAN: slab-use-after-free in __locks_delete_block\n    __locks_delete_block\n    locks_delete_block\n    ksmbd_vfs_posix_lock_unblock\n    smb2_remove_blocked_lock\n    smb2_cancel                 \u003c- 2nd SMB2_CANCEL fires cancel_fn\n    handle_ksmbd_work\n  Allocated by ...: locks_alloc_lock \u003c- smb2_lock\n  Freed by ...:     locks_free_lock  \u003c- smb2_lock (non-ACTIVE early-exit)\n  ... cache file_lock_cache of size 192\n\nReproduced on mainline 7.1-rc7 (which already contains f580d27e8928) with\nKASAN by an authenticated SMB client; the double-SMB2_CANCEL control is\nsilent on that kernel, so the splat is attributable to the CLOSE trigger.\n\nOnly an ACTIVE deferred work may have its cancel_fn fired: both terminal\nstates (CANCELLED and CLOSED) reach the smb2_lock() early-exit that frees\nthe file_lock and skips release_async_work(). Guard on KSMBD_WORK_ACTIVE\nso any non-active work is skipped.",
  "id": "GHSA-x5p7-hg5v-9p54",
  "modified": "2026-07-25T12:31:35Z",
  "published": "2026-07-25T12:31:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-64437"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/10f293a07f9e10e988b0ae44e2e99c631f5a68e0"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/12c36c99655f325befe50c26842f7deca414c381"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/94083db751930b1540ddff2b54d4677549c57f81"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a796ba4e61d5e14e07b79a359faac69f8f9b22a3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b8e274e69ab09222c7a552c7c0c1eef9ce627fc1"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ddb9239828336b36d8a3ef5943fdffb2f55b6508"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

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Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.

Action not permitted

CVE-2026-64437 (GCVE-0-2026-64437)

GHSA-X5P7-HG5V-9P54

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