CVE-2021-28691 (GCVE-0-2021-28691)

Vulnerability from cvelistv5 – Published: 2021-06-29 11:30 – Updated: 2024-08-03 21:47
VLAI
Summary
Guest triggered use-after-free in Linux xen-netback A malicious or buggy network PV frontend can force Linux netback to disable the interface and terminate the receive kernel thread associated with queue 0 in response to the frontend sending a malformed packet. Such kernel thread termination will lead to a use-after-free in Linux netback when the backend is destroyed, as the kernel thread associated with queue 0 will have already exited and thus the call to kthread_stop will be performed against a stale pointer.
Severity
No CVSS data available.
CWE
  • unknown
Assigner
XEN CNA under the mitre root
CNA scorecard D 56/100 over 46 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Unknown: unspecified , < 4.12 (custom)
Affected: 5.5.0 , < unspecified (custom)
Unaffected: next of 5.12.2 , < unspecified (custom)
guessed Create a notification for this product.
Credits
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      "id": "CVE-2021-28691",
      "initial_release_date": "2021-06-08T00:00:00+00:00",
      "product_status:known_not_affected": "1",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "xen: guest triggered use-after-free in Linux xen-netback (XSA-374)",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-28691.json",
      "version": "3"
    }
  }
}



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Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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    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.