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)
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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)
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      "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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Tags
Taxonomy of the tags.





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.



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.