cvelist/2023/46xxx/CVE-2023-46841.json

{
    "data_version": "4.0",
    "data_type": "CVE",
    "data_format": "MITRE",
    "CVE_data_meta": {
        "ID": "CVE-2023-46841",
        "ASSIGNER": "security@xen.org",
        "STATE": "PUBLIC"
    },
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "Recent x86 CPUs offer functionality named Control-flow Enforcement\nTechnology (CET).  A sub-feature of this are Shadow Stacks (CET-SS).\nCET-SS is a hardware feature designed to protect against Return Oriented\nProgramming attacks. When enabled, traditional stacks holding both data\nand return addresses are accompanied by so called \"shadow stacks\",\nholding little more than return addresses.  Shadow stacks aren't\nwritable by normal instructions, and upon function returns their\ncontents are used to check for possible manipulation of a return address\ncoming from the traditional stack.\n\nIn particular certain memory accesses need intercepting by Xen.  In\nvarious cases the necessary emulation involves kind of replaying of\nthe instruction.  Such replaying typically involves filling and then\ninvoking of a stub.  Such a replayed instruction may raise an\nexceptions, which is expected and dealt with accordingly.\n\nUnfortunately the interaction of both of the above wasn't right:\nRecovery involves removal of a call frame from the (traditional) stack.\nThe counterpart of this operation for the shadow stack was missing.\n"
            }
        ]
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "n/a"
                    }
                ]
            }
        ]
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "vendor_name": "Xen",
                    "product": {
                        "product_data": [
                            {
                                "product_name": "Xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "not down converted",
                                            "x_cve_json_5_version_data": {
                                                "versions": [
                                                    {
                                                        "status": "unknown",
                                                        "version": "consult Xen advisory XSA-451"
                                                    }
                                                ],
                                                "defaultStatus": "unknown"
                                            }
                                        }
                                    ]
                                }
                            }
                        ]
                    }
                }
            ]
        }
    },
    "references": {
        "reference_data": [
            {
                "url": "https://xenbits.xenproject.org/xsa/advisory-451.html",
                "refsource": "MISC",
                "name": "https://xenbits.xenproject.org/xsa/advisory-451.html"
            },
            {
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZON4TLXG7TG4A2XZG563JMVTGQW4SF3A/",
                "refsource": "MISC",
                "name": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZON4TLXG7TG4A2XZG563JMVTGQW4SF3A/"
            }
        ]
    },
    "configuration": [
        {
            "lang": "en",
            "value": "Xen 4.14 and onwards are vulnerable.  Xen 4.13 and older are not\nvulnerable.\n\nOnly x86 systems with CET-SS enabled are vulnerable.  x86 systems with\nCET-SS unavailable or disabled are not vulnerable.  Arm systems are not\nvulnerable.  See\nhttps://xenbits.xen.org/docs/latest/faq.html#tell-if-cet-is-active\nfor how to determine whether CET-SS is active.\n\nOnly HVM or PVH guests can leverage the vulnerability.  PV guests cannot\nleverage the vulnerability.\n"
        }
    ],
    "work_around": [
        {
            "lang": "en",
            "value": "While in principle it is possible to disable use of CET on capable\nsystems using the \"cet=no-shstk\" command line option, doing so disables\nan important security feature and may therefore not be advisable.\n"
        }
    ],
    "credits": [
        {
            "lang": "en",
            "value": "This issue was discovered by Jan Beulich of SUSE.\n"
        }
    ]
}