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CVE-2026-31678 (GCVE-0-2026-31678)

Vulnerability from cvelistv5 – Published: 2026-04-25 08:46 – Updated: 2026-08-05 12:24
VLAI
Title
openvswitch: defer tunnel netdev_put to RCU release
Summary
In the Linux kernel, the following vulnerability has been resolved: openvswitch: defer tunnel netdev_put to RCU release ovs_netdev_tunnel_destroy() may run after NETDEV_UNREGISTER already detached the device. Dropping the netdev reference in destroy can race with concurrent readers that still observe vport->dev. Do not release vport->dev in ovs_netdev_tunnel_destroy(). Instead, let vport_netdev_free() drop the reference from the RCU callback, matching the non-tunnel destroy path and avoiding additional synchronization under RTNL.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < 9d56aced21fb9c104e8a3f3be9b21fbafe448ffc (git)
Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < 42f0d3d81209654c08ffdde5a34b9b92d2645896 (git)
Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < bbe7bd722bfaea36aab3da6cc60fb4a05c644643 (git)
Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < 98b726ab5e2a4811e27c28e4d041f75bba147eab (git)
Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < b8c56a3fc5d879c0928f207a756b0f067f06c6a8 (git)
Affected: a9020fde67a6eb77f8130feff633189f99264db1 , < 6931d21f87bc6d657f145798fad0bf077b82486c (git)
guessed Create a notification for this product.
Linux Linux Affected: 4.3
Unaffected: 0 , < 4.3 (semver)
Unaffected: 6.1.168 , ≤ 6.1.* (semver)
Unaffected: 6.6.131 , ≤ 6.6.* (semver)
Unaffected: 6.12.80 , ≤ 6.12.* (semver)
Unaffected: 6.18.21 , ≤ 6.18.* (semver)
Unaffected: 6.19.11 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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    "redhat_vex": {
      "aggregate_severity": "Important",
      "current_release_date": "2026-09-03T12:21:09+00:00",
      "cve": "CVE-2026-31678",
      "id": "CVE-2026-31678",
      "initial_release_date": "2026-04-25T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:known_not_affected": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: openvswitch: defer tunnel netdev_put to RCU release",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31678.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-16T00:15:02Z",
      "cve": "CVE-2026-31678",
      "id": "CVE-2026-31678",
      "initial_release_date": "2026-04-26T01:52:42Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "644",
      "product_status:known_not_affected": "4",
      "product_status:recommended": "316",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-31678",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-31678.json",
      "version": "31"
    }
  }
}



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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • 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.


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