CVE-2022-42332 (GCVE-0-2022-42332)

Vulnerability from cvelistv5 – Published: 2023-03-21 00:00 – Updated: 2025-02-13 16:33
VLAI
Summary
x86 shadow plus log-dirty mode use-after-free In environments where host assisted address translation is necessary but Hardware Assisted Paging (HAP) is unavailable, Xen will run guests in so called shadow mode. Shadow mode maintains a pool of memory used for both shadow page tables as well as auxiliary data structures. To migrate or snapshot guests, Xen additionally runs them in so called log-dirty mode. The data structures needed by the log-dirty tracking are part of aformentioned auxiliary data. In order to keep error handling efforts within reasonable bounds, for operations which may require memory allocations shadow mode logic ensures up front that enough memory is available for the worst case requirements. Unfortunately, while page table memory is properly accounted for on the code path requiring the potential establishing of new shadows, demands by the log-dirty infrastructure were not taken into consideration. As a result, just established shadow page tables could be freed again immediately, while other code is still accessing them on the assumption that they would remain allocated.
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-12-03 15:13 UTC
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
Xen xen Unknown: consult Xen advisory XSA-427
guessed Create a notification for this product.
Credits
{'credit_data': {'description': {'description_data': [{'lang': 'eng', 'value': 'This issue was discovered by Jan Beulich of SUSE.'}]}}}
Show details on NVD website
To clipboard 

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              "url": "https://www.debian.org/security/2023/dsa-5378"
            },
            {
              "url": "https://security.gentoo.org/glsa/202402-07"
            }
          ]
        }
      },
      "cveMetadata": {
        "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "assignerShortName": "XEN",
        "cveId": "CVE-2022-42332",
        "datePublished": "2023-03-21T00:00:00",
        "dateReserved": "2022-10-03T00:00:00",
        "dateUpdated": "2024-12-03T15:13:35.957Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}



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Drag nodes to arrange them. Double-click a related vulnerability to open it, or a source to visit its link. The Physics button on the left tunes the layout and the simulation; the legend at the bottom left hides or shows nodes by kind and by sighting type.

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.
Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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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.