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            "url": "https://xenbits.xenproject.org/xsa/advisory-390.txt"
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          },
          {
            "name": "GLSA-202208-23",
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            ],
            "url": "https://security.gentoo.org/glsa/202208-23"
          }
        ],
        "title": "CVE Program Container"
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    "cna": {
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          "vendor": "Xen",
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          "value": "{\u0027credit_data\u0027: {\u0027description\u0027: {\u0027description_data\u0027: [{\u0027lang\u0027: \u0027eng\u0027, \u0027value\u0027: \u0027This issue was discovered by Jan Beulich of SUSE.\u0027}]}}}"
        }
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          "value": "certain VT-d IOMMUs may not work in shared page table mode For efficiency reasons, address translation control structures (page tables) may (and, on suitable hardware, by default will) be shared between CPUs, for second-level translation (EPT), and IOMMUs. These page tables are presently set up to always be 4 levels deep. However, an IOMMU may require the use of just 3 page table levels. In such a configuration the lop level table needs to be stripped before inserting the root table\u0027s address into the hardware pagetable base register. When sharing page tables, Xen erroneously skipped this stripping. Consequently, the guest is able to write to leaf page table entries."
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                    "lang": "eng",
                    "value": "A malicious guest may be able to escalate its privileges to that of\nthe host."
                  }
                ]
              }
            },
            "type": "unknown"
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              "description": "unknown",
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        "dateUpdated": "2022-08-14T20:09:18",
        "orgId": "23aa2041-22e1-471f-9209-9b7396fa234f",
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                  "value": "Suppressing the use of shared page tables avoids the vulnerability.\nThis can be achieved globally by passing \"iommu=no-sharept\" on the\nhypervisor command line.  This can also be achieved on a per-guest basis\nvia the \"passthrough=sync_pt\" xl guest configuration file option."
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    "dateReserved": "2021-03-18T00:00:00",
    "dateUpdated": "2024-08-03T21:47:33.159Z",
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