certfr_avis - certfr-2023-avi-0938

CERTFR-2023-AVI-0938

Vulnerability from certfr_avis

De multiples vulnérabilités ont été découvertes dans Xen. Elles permettent à un attaquant de provoquer une atteinte à la confidentialité des données et un contournement de la politique de sécurité.

Solution

Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation).

None

Impacted products

Vendor	Product	Description
XEN	Xen	Xen versions 4.16.x sans le dernier correctif de sécurité
XEN	Xen	Xen versions 4.15.x sans le dernier correctif de sécurité
XEN	Xen	Xen versions 4.17.x sans le dernier correctif de sécurité

References

Title

Publication Time

Tags

Bulletin de sécurité Xen advisory-445 du 14 novembre 2023	None	vendor-advisory
Bulletin de sécurité Xen advisory-446 du 14 novembre 2023	None	vendor-advisory
Bulletin de sécurité Xen advisory-446 du 14 novembre 2023	-	other
Bulletin de sécurité Xen advisory-445 du 14 novembre 2023	-	other

Show details on source website

JSON

To clipboard

{
  "$ref": "https://www.cert.ssi.gouv.fr/openapi.json",
  "affected_systems": [
    {
      "description": "Xen versions 4.16.x sans le dernier correctif de s\u00e9curit\u00e9",
      "product": {
        "name": "Xen",
        "vendor": {
          "name": "XEN",
          "scada": false
        }
      }
    },
    {
      "description": "Xen versions 4.15.x sans le dernier correctif de s\u00e9curit\u00e9",
      "product": {
        "name": "Xen",
        "vendor": {
          "name": "XEN",
          "scada": false
        }
      }
    },
    {
      "description": "Xen versions 4.17.x sans le dernier correctif de s\u00e9curit\u00e9",
      "product": {
        "name": "Xen",
        "vendor": {
          "name": "XEN",
          "scada": false
        }
      }
    }
  ],
  "affected_systems_content": null,
  "content": "## Solution\n\nSe r\u00e9f\u00e9rer au bulletin de s\u00e9curit\u00e9 de l\u0027\u00e9diteur pour l\u0027obtention des\ncorrectifs (cf. section Documentation).\n",
  "cves": [
    {
      "name": "CVE-2023-46835",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-46835"
    },
    {
      "name": "CVE-2023-46836",
      "url": "https://www.cve.org/CVERecord?id=CVE-2023-46836"
    }
  ],
  "initial_release_date": "2023-11-15T00:00:00",
  "last_revision_date": "2023-11-15T00:00:00",
  "links": [
    {
      "title": "Bulletin de s\u00e9curit\u00e9 Xen\u00a0advisory-446 du 14 novembre 2023",
      "url": "https://xenbits.xen.org/xsa/advisory-446.html"
    },
    {
      "title": "Bulletin de s\u00e9curit\u00e9 Xen\u00a0advisory-445 du 14 novembre 2023",
      "url": "https://xenbits.xen.org/xsa/advisory-445.html"
    }
  ],
  "reference": "CERTFR-2023-AVI-0938",
  "revisions": [
    {
      "description": "Version initiale",
      "revision_date": "2023-11-15T00:00:00.000000"
    }
  ],
  "risks": [
    {
      "description": "Contournement de la politique de s\u00e9curit\u00e9"
    },
    {
      "description": "Atteinte \u00e0 la confidentialit\u00e9 des donn\u00e9es"
    }
  ],
  "summary": "De multiples vuln\u00e9rabilit\u00e9s ont \u00e9t\u00e9 d\u00e9couvertes dans\u003cspan\nclass=\"textit\"\u003e Xen\u003c/span\u003e. Elles permettent \u00e0 un attaquant de provoquer\nune atteinte \u00e0 la confidentialit\u00e9 des donn\u00e9es et un contournement de la\npolitique de s\u00e9curit\u00e9.\n",
  "title": "Multiples vuln\u00e9rabilit\u00e9s dans Xen",
  "vendor_advisories": [
    {
      "published_at": null,
      "title": "Bulletin de s\u00e9curit\u00e9 Xen advisory-445 du 14 novembre 2023",
      "url": null
    },
    {
      "published_at": null,
      "title": "Bulletin de s\u00e9curit\u00e9 Xen advisory-446 du 14 novembre 2023",
      "url": null
    }
  ]
}

CVE-2023-46836 (GCVE-0-2023-46836)

Vulnerability from cvelistv5

Published

2024-01-05 16:34

Modified

2025-06-03 14:40

Severity ?

4.7 (Medium) - CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N

Summary

The fixes for XSA-422 (Branch Type Confusion) and XSA-434 (Speculative Return Stack Overflow) are not IRQ-safe. It was believed that the mitigations always operated in contexts with IRQs disabled. However, the original XSA-254 fix for Meltdown (XPTI) deliberately left interrupts enabled on two entry paths; one unconditionally, and one conditionally on whether XPTI was active. As BTC/SRSO and Meltdown affect different CPU vendors, the mitigations are not active together by default. Therefore, there is a race condition whereby a malicious PV guest can bypass BTC/SRSO protections and launch a BTC/SRSO attack against Xen.

References

URL

Tags

https://xenbits.xenproject.org/xsa/advisory-446.html

Impacted products

	Vendor	Product	Version
	Xen	Xen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T20:53:21.940Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://xenbits.xenproject.org/xsa/advisory-446.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "HIGH",
              "attackVector": "LOCAL",
              "availabilityImpact": "NONE",
              "baseScore": 4.7,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2023-46836",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-05-08T20:16:12.540203Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "description": "CWE-noinfo Not enough information",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-06-03T14:40:56.728Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-446"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All versions of Xen are vulnerable.\n\nXen is only vulnerable in default configurations on AMD and Hygon CPUs.\n\nXen is not believed to be vulnerable in default configurations on CPUs\nfrom other hardware vendors.\n\nOnly PV guests can leverage the vulnerability.\n"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "This issue was discovered by Andrew Cooper of XenServer.\n"
        }
      ],
      "datePublic": "2023-11-14T12:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "The fixes for XSA-422 (Branch Type Confusion) and XSA-434 (Speculative\nReturn Stack Overflow) are not IRQ-safe.  It was believed that the\nmitigations always operated in contexts with IRQs disabled.\n\nHowever, the original XSA-254 fix for Meltdown (XPTI) deliberately left\ninterrupts enabled on two entry paths; one unconditionally, and one\nconditionally on whether XPTI was active.\n\nAs BTC/SRSO and Meltdown affect different CPU vendors, the mitigations\nare not active together by default.  Therefore, there is a race\ncondition whereby a malicious PV guest can bypass BTC/SRSO protections\nand launch a BTC/SRSO attack against Xen.\n"
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "An attacker in a PV guest might be able to infer the contents of memory\nbelonging to other guests.\n"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2024-01-05T16:34:59.036Z",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN"
      },
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-446.html"
        }
      ],
      "title": "x86: BTC/SRSO fixes not fully effective",
      "workarounds": [
        {
          "lang": "en",
          "value": "Running only HVM or PVH VMs will avoid the vulnerability.\n"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "cveId": "CVE-2023-46836",
    "datePublished": "2024-01-05T16:34:59.036Z",
    "dateReserved": "2023-10-27T07:55:35.332Z",
    "dateUpdated": "2025-06-03T14:40:56.728Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

CVE-2023-46835 (GCVE-0-2023-46835)

Vulnerability from cvelistv5

Published

2024-01-05 16:34

Modified

2025-06-17 16:11

Severity ?

5.5 (Medium) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Summary

The current setup of the quarantine page tables assumes that the quarantine domain (dom_io) has been initialized with an address width of DEFAULT_DOMAIN_ADDRESS_WIDTH (48) and hence 4 page table levels. However dom_io being a PV domain gets the AMD-Vi IOMMU page tables levels based on the maximum (hot pluggable) RAM address, and hence on systems with no RAM above the 512GB mark only 3 page-table levels are configured in the IOMMU. On systems without RAM above the 512GB boundary amd_iommu_quarantine_init() will setup page tables for the scratch page with 4 levels, while the IOMMU will be configured to use 3 levels only, resulting in the last page table directory (PDE) effectively becoming a page table entry (PTE), and hence a device in quarantine mode gaining write access to the page destined to be a PDE. Due to this page table level mismatch, the sink page the device gets read/write access to is no longer cleared between device assignment, possibly leading to data leaks.

References

URL

Tags

https://xenbits.xenproject.org/xsa/advisory-445.html

Impacted products

	Vendor	Product	Version
	Xen	Xen

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "providerMetadata": {
          "dateUpdated": "2024-08-02T20:53:21.879Z",
          "orgId": "af854a3a-2127-422b-91ae-364da2661108",
          "shortName": "CVE"
        },
        "references": [
          {
            "tags": [
              "x_transferred"
            ],
            "url": "https://xenbits.xenproject.org/xsa/advisory-445.html"
          }
        ],
        "title": "CVE Program Container"
      },
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "LOCAL",
              "availabilityImpact": "NONE",
              "baseScore": 5.5,
              "baseSeverity": "MEDIUM",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "LOW",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2023-46835",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2024-04-12T04:00:28.791183Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-787",
                "description": "CWE-787 Out-of-bounds Write",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-06-17T16:11:08.422Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Xen",
          "vendor": "Xen",
          "versions": [
            {
              "status": "unknown",
              "version": "consult Xen advisory XSA-445"
            }
          ]
        }
      ],
      "configurations": [
        {
          "lang": "en",
          "value": "All Xen versions supporting PCI passthrough are affected.\n\nOnly x86 AMD systems with IOMMU hardware are vulnerable.\n\nOnly x86 guests which have physical devices passed through to them can\nleverage the vulnerability.\n"
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "This issue was discovered by Roger Pau Monn\u00e9 of XenServer.\n"
        }
      ],
      "datePublic": "2023-11-14T12:00:00.000Z",
      "descriptions": [
        {
          "lang": "en",
          "value": "The current setup of the quarantine page tables assumes that the\nquarantine domain (dom_io) has been initialized with an address width\nof DEFAULT_DOMAIN_ADDRESS_WIDTH (48) and hence 4 page table levels.\n\nHowever dom_io being a PV domain gets the AMD-Vi IOMMU page tables\nlevels based on the maximum (hot pluggable) RAM address, and hence on\nsystems with no RAM above the 512GB mark only 3 page-table levels are\nconfigured in the IOMMU.\n\nOn systems without RAM above the 512GB boundary\namd_iommu_quarantine_init() will setup page tables for the scratch\npage with 4 levels, while the IOMMU will be configured to use 3 levels\nonly, resulting in the last page table directory (PDE) effectively\nbecoming a page table entry (PTE), and hence a device in quarantine\nmode gaining write access to the page destined to be a PDE.\n\nDue to this page table level mismatch, the sink page the device gets\nread/write access to is no longer cleared between device assignment,\npossibly leading to data leaks.\n"
        }
      ],
      "impacts": [
        {
          "descriptions": [
            {
              "lang": "en",
              "value": "A device in quarantine mode can access data from previous quarantine\npage table usages, possibly leaking data used by previous domains that\nalso had the device assigned.\n"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2024-01-05T16:34:49.531Z",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
        "shortName": "XEN"
      },
      "references": [
        {
          "url": "https://xenbits.xenproject.org/xsa/advisory-445.html"
        }
      ],
      "title": "x86/AMD: mismatch in IOMMU quarantine page table levels",
      "workarounds": [
        {
          "lang": "en",
          "value": "Not passing through physical devices to guests will avoid the\nvulnerability.\n\nNot using quarantine scratch-page mode will avoid the vulnerability,\nbut could result in other issues.\n"
        }
      ]
    }
  },
  "cveMetadata": {
    "assignerOrgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
    "assignerShortName": "XEN",
    "cveId": "CVE-2023-46835",
    "datePublished": "2024-01-05T16:34:49.531Z",
    "dateReserved": "2023-10-27T07:55:35.331Z",
    "dateUpdated": "2025-06-17T16:11:08.422Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Tags

Taxonomy of the tags.

All sightings related to this event Export sightings related to this event

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

Action not permitted

CERTFR-2023-AVI-0938

Vulnerability from certfr_avis

Solution

CVE-2023-46836 (GCVE-0-2023-46836)

Vulnerability from cvelistv5

CVE-2023-46835 (GCVE-0-2023-46835)

Vulnerability from cvelistv5

Tags

Sightings

Nomenclature