CVE-2026-64061 (GCVE-0-2026-64061)

Vulnerability from cvelistv5 – Published: 2026-07-19 15:39 – Updated: 2026-08-05 12:38
VLAI
Title
netfs: Fix early put of sink folio in netfs_read_gaps()
Summary
In the Linux kernel, the following vulnerability has been resolved: netfs: Fix early put of sink folio in netfs_read_gaps() Fix netfs_read_gaps() to release the sink page it uses after waiting for the request to complete. The way the sink page is used is that an ITER_BVEC-class iterator is created that has the gaps from the target folio at either end, but has the sink page tiled over the middle so that a single read op can fill in both gaps. The bug was found by KASAN detecting a UAF on the generic/075 xfstest in the cifsd kernel thread that handles reception of data from the TCP socket: BUG: KASAN: use-after-free in _copy_to_iter+0x48a/0xa20 Write of size 885 at addr ffff888107f92000 by task cifsd/1285 CPU: 2 UID: 0 PID: 1285 Comm: cifsd Not tainted 7.0.0 #6 PREEMPT(lazy) Call Trace: dump_stack_lvl+0x5d/0x80 print_report+0x17f/0x4f1 kasan_report+0x100/0x1e0 kasan_check_range+0x10f/0x1e0 __asan_memcpy+0x3c/0x60 _copy_to_iter+0x48a/0xa20 __skb_datagram_iter+0x2c9/0x430 skb_copy_datagram_iter+0x6e/0x160 tcp_recvmsg_locked+0xce0/0x1130 tcp_recvmsg+0xeb/0x300 inet_recvmsg+0xcf/0x3a0 sock_recvmsg+0xea/0x100 cifs_readv_from_socket+0x3a6/0x4d0 [cifs] cifs_read_iter_from_socket+0xdd/0x130 [cifs] cifs_readv_receive+0xaad/0xb10 [cifs] cifs_demultiplex_thread+0x1148/0x1740 [cifs] kthread+0x1cf/0x210
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 , < 2a39d49c8d97df8cb8fa80c10859bc1ba7358c6b (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < d4f4bc87c76511cf2532448b0fa40c25e894bd7d (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < 412e8bad48967fd34295866636c028befd27d8b9 (git)
Affected: ee4cdf7ba857a894ad1650d6ab77669cbbfa329e , < 3e5dd91b87a8b1450217b56a336bee315f40da7d (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.12
Unaffected: 0 , < 6.12 (semver)
Unaffected: 6.12.92 , ≤ 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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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfs: Fix early put of sink folio in netfs_read_gaps()\n\nFix netfs_read_gaps() to release the sink page it uses after waiting for\nthe request to complete.  The way the sink page is used is that an\nITER_BVEC-class iterator is created that has the gaps from the target folio\nat either end, but has the sink page tiled over the middle so that a single\nread op can fill in both gaps.\n\nThe bug was found by KASAN detecting a UAF on the generic/075 xfstest in\nthe cifsd kernel thread that handles reception of data from the TCP socket:\n\n BUG: KASAN: use-after-free in _copy_to_iter+0x48a/0xa20\n Write of size 885 at addr ffff888107f92000 by task cifsd/1285\n CPU: 2 UID: 0 PID: 1285 Comm: cifsd Not tainted 7.0.0 #6 PREEMPT(lazy)\n Call Trace:\n  dump_stack_lvl+0x5d/0x80\n  print_report+0x17f/0x4f1\n  kasan_report+0x100/0x1e0\n  kasan_check_range+0x10f/0x1e0\n  __asan_memcpy+0x3c/0x60\n  _copy_to_iter+0x48a/0xa20\n  __skb_datagram_iter+0x2c9/0x430\n  skb_copy_datagram_iter+0x6e/0x160\n  tcp_recvmsg_locked+0xce0/0x1130\n  tcp_recvmsg+0xeb/0x300\n  inet_recvmsg+0xcf/0x3a0\n  sock_recvmsg+0xea/0x100\n  cifs_readv_from_socket+0x3a6/0x4d0 [cifs]\n  cifs_read_iter_from_socket+0xdd/0x130 [cifs]\n  cifs_readv_receive+0xaad/0xb10 [cifs]\n  cifs_demultiplex_thread+0x1148/0x1740 [cifs]\n  kthread+0x1cf/0x210"
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        "id": "CVE-2026-64061",
        "lastModified": "2026-09-02T21:12:26.360",
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                "attackVector": "NETWORK",
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                "confidentialityImpact": "HIGH",
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        "vulnStatus": "Analyzed",
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              {
                "lang": "en",
                "value": "CWE-416"
              }
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            "source": "nvd@nist.gov",
            "type": "Primary"
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    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-07-20T15:27:28+00:00",
      "cve": "CVE-2026-64061",
      "id": "CVE-2026-64061",
      "initial_release_date": "2026-07-19T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "199",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: netfs: Fix early put of sink folio in netfs_read_gaps()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-64061.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-10T16:47:48Z",
      "cve": "CVE-2026-64061",
      "id": "CVE-2026-64061",
      "initial_release_date": "2026-07-21T13:00:24Z",
      "product_status:first_fixed": "2",
      "product_status:known_not_affected": "345",
      "product_status:recommended": "145",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-64061",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-64061.json",
      "version": "12"
    }
  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.