CVE-2026-43378 (GCVE-0-2026-43378)

Vulnerability from cvelistv5 – Published: 2026-05-08 14:21 – Updated: 2026-08-05 12:27
VLAI
Title
smb: server: fix use-after-free in smb2_open()
Summary
In the Linux kernel, the following vulnerability has been resolved: smb: server: fix use-after-free in smb2_open() The opinfo pointer obtained via rcu_dereference(fp->f_opinfo) is dereferenced after rcu_read_unlock(), creating a use-after-free window.
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: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < e1b21e6066615e7d3d3a7aa2677e415e563fd7cc (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < b720c84087cb547f23ce03eab93568c1769e4556 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 54b48ae83de8bb06e65079d96368efe359d4909c (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 8f5b1a7cb009a93c48e9e334a2f59a660f9afc07 (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 190e5f808e8058640b408ccfed25440b441a718a (git)
Affected: e2f34481b24db2fd634b5edb0a5bd0e4d38cc6e9 , < 1e689a56173827669a35da7cb2a3c78ed5c53680 (git)
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Linux Linux Affected: 5.15
Unaffected: 0 , < 5.15 (semver)
Unaffected: 6.1.167 , ≤ 6.1.* (semver)
Unaffected: 6.6.130 , ≤ 6.6.* (semver)
Unaffected: 6.12.78 , ≤ 6.12.* (semver)
Unaffected: 6.18.19 , ≤ 6.18.* (semver)
Unaffected: 6.19.9 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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    "redhat_vex": {
      "aggregate_severity": "None",
      "current_release_date": "2026-06-28T06:33:54+00:00",
      "cve": "CVE-2026-43378",
      "id": "CVE-2026-43378",
      "initial_release_date": "2026-05-08T00:00:00+00:00",
      "product_status:known_not_affected": "274",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: smb: server: fix use-after-free in smb2_open()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43378.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-08-06T01:20:14Z",
      "cve": "CVE-2026-43378",
      "id": "CVE-2026-43378",
      "initial_release_date": "2026-05-13T03:34:40Z",
      "product_status:known_affected": "30",
      "product_status:known_not_affected": "263",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-43378",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-43378.json",
      "version": "5"
    }
  }
}



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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.

Sightings

Author Source Type Date Other

Nomenclature

  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.