{
  "cveId": "CVE-2026-89646",
  "url": "https://patchblox.com/security/cve/CVE-2026-89646",
  "summary": "CVE-2026-89646 is fixed in 20 products on 1 platform, first by DEBIAN-CVE-2026-89646, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  ceph: fix leaked inode reference on writeback ab...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  ceph: fix leaked inode reference on writeback abort at umount  ceph_dirty_folio() takes a wrbuffer claim on each newly dirtied folio: it bumps i_wrbuffer_ref (taking an ihold() on the 0-\u003E1 transition) and attaches the snap_context to folio-\u003Eprivate.  That claim is released only by ceph_put_wrbuffer_cap_refs(), which for a submitted write runs from writepages_finish().  In ceph_submit_write(), if ceph_inc_osd_stopping_blocker() fails -- which happens during umount -- the request is aborted before submission: the already-collected folios are only redirtied and unlocked, so writepages_finish() never runs and the claim is leaked. redirty_page_for_writepage() -\u003E folio_redirty_for_writepage() -\u003E filemap_dirty_folio() sets PG_dirty directly and does not go through -\u003Edirty_folio, so ceph_dirty_folio() is not re-entered to rebalance it. Because every subsequent writeback also fails the osd_stopping_blocker, i_wrbuffer_ref never returns to 0, the ihold() is never dropped, and the inode cannot be evicted:    VFS: Busy inodes after unmount of ceph   kernel BUG at fs/super.c:650!  Release the orphaned claim in the abort path before redirtying, via ceph_undo_wrbuffer_claim(): detach the snap_context, drop the wrbuffer reference (letting i_wrbuffer_ref reach 0 and iput() the inode), and drop the snap_context reference -- i.e. do what writepages_finish() would have done for these never-submitted folios.  Only the locked_pages entries are undone; folios still in the fbatch were never dirty-cleared by this call (folio_clear_dirty_for_io() is the ownership-transfer point, and a successful move NULLs the fbatch slot), so they hold no claim this call owns.",
  "published": "2026-09-11T20:19:50Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00173,
  "epssPercentile": 0.06804,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "bpftool6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "bpftool6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel-livepatch-6.18.51-120.162",
      "release": "amzn 2023",
      "fixedVersion": "1:1.0-0.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-aarch64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-debuginfo-common-x86_64",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-headers",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-modules-extra-common",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "kernel6.18-tools-devel",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.6-1",
      "fix": "DEBIAN-CVE-2026-89646",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-89646",
      "released": "2026-09-23T19:19:02Z"
    },
    {
      "platform": "linux",
      "product": "microvm-kernel6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
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      "product": "perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    },
    {
      "platform": "linux",
      "product": "python3-perf6.18-debuginfo",
      "release": "amzn 2023",
      "fixedVersion": "1:6.18.51-120.162.amzn2023",
      "fix": "ALAS2023-2026-3187",
      "url": "https://patchblox.com/security/fix/linux/alas2023-2026-3187",
      "released": "2026-11-07T01:06:52Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}