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CVE-2026-64216 (GCVE-0-2026-64216)

Vulnerability from cvelistv5 – Published: 2026-07-24 15:23 – Updated: 2026-08-27 12:39
VLAI
Title
netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages()
Summary
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix potential UAF in netfs_unlock_abandoned_read_pages() netfs_unlock_abandoned_read_pages(rreq) accesses the index of the folios it is wanting to unlock and compares that to rreq->no_unlock_folio so that it doesn't unlock a folio being read for netfs_perform_write() or netfs_write_begin(). However, given that netfs_unlock_abandoned_read_pages() is called _after_ NETFS_RREQ_IN_PROGRESS is cleared, the one folio that it's not allowed to dereference is the one specified by ->no_unlock_folio as ownership immediately reverts to the caller. Fix this by storing the folio pointer instead and using that rather than the index. Also fix netfs_unlock_read_folio() where the same applies.
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < d4ae8dba90b89e7bb4d1045d1cb26afbaf13ee5c (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < 6080fa3ecfbb4448a3b47368629534c09b6ec750 (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < 3866d015f33aeedf81338dd99154703bef33faef (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < dbe556972100fabb8e5a1b3d2163831ff07b1e8e (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.106 , ≤ 6.12.* (semver)
Unaffected: 6.18.34 , ≤ 6.18.* (semver)
Unaffected: 7.0.11 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-08-13T16:45:20+00:00",
      "cve": "CVE-2026-64216",
      "id": "CVE-2026-64216",
      "initial_release_date": "2026-07-24T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "199",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Kernel: netfs Use-After-Free vulnerability allows local denial of service and memory corruption",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64216.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-10T02:26:32Z",
      "cve": "CVE-2026-64216",
      "id": "CVE-2026-64216",
      "initial_release_date": "2026-07-25T00:14:22Z",
      "product_status:known_affected": "17",
      "product_status:known_not_affected": "347",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64216",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64216.json",
      "version": "7"
    }
  }
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.