cvelist/2021/28xxx/CVE-2021-28705.json

{
    "CVE_data_meta": {
        "ASSIGNER": "security@xen.org",
        "ID": "CVE-2021-28705",
        "STATE": "PUBLIC"
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "product": {
                        "product_data": [
                            {
                                "product_name": "xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "4.14.x"
                                        }
                                    ]
                                }
                            },
                            {
                                "product_name": "xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "4.12.x"
                                        }
                                    ]
                                }
                            },
                            {
                                "product_name": "xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "4.15.x"
                                        }
                                    ]
                                }
                            },
                            {
                                "product_name": "xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "xen-unstable"
                                        }
                                    ]
                                }
                            },
                            {
                                "product_name": "xen",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_value": "4.13.x"
                                        }
                                    ]
                                }
                            }
                        ]
                    },
                    "vendor_name": "Xen"
                }
            ]
        }
    },
    "configuration": {
        "configuration_data": {
            "description": {
                "description_data": [
                    {
                        "lang": "eng",
                        "value": "All Xen versions from 3.4 onwards are affected.  Xen versions 3.3 and\nolder are believed to not be affected.\n\nOnly x86 HVM and PVH guests started in populate-on-demand mode are\nbelieved to be able to leverage the vulnerability.  Populate-on-demand\nmode is activated when the guest's xl configuration file specifies a\n\"maxmem\" value which is larger than the \"memory\" value."
                    }
                ]
            }
        }
    },
    "credit": {
        "credit_data": {
            "description": {
                "description_data": [
                    {
                        "lang": "eng",
                        "value": "This issue was discovered by Jan Beulich of SUSE."
                    }
                ]
            }
        }
    },
    "data_format": "MITRE",
    "data_type": "CVE",
    "data_version": "4.0",
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "issues with partially successful P2M updates on x86 T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] x86 HVM and PVH guests may be started in populate-on-demand (PoD) mode, to provide a way for them to later easily have more memory assigned. Guests are permitted to control certain P2M aspects of individual pages via hypercalls. These hypercalls may act on ranges of pages specified via page orders (resulting in a power-of-2 number of pages). In some cases the hypervisor carries out the requests by splitting them into smaller chunks. Error handling in certain PoD cases has been insufficient in that in particular partial success of some operations was not properly accounted for. There are two code paths affected - page removal (CVE-2021-28705) and insertion of new pages (CVE-2021-28709). (We provide one patch which combines the fix to both issues.)"
            }
        ]
    },
    "impact": {
        "impact_data": {
            "description": {
                "description_data": [
                    {
                        "lang": "eng",
                        "value": "Malicious or buggy guest kernels may be able to mount a Denial of\nService (DoS) attack affecting the entire system.  Privilege escalation\nand information leaks cannot be ruled out."
                    }
                ]
            }
        }
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "unknown"
                    }
                ]
            }
        ]
    },
    "references": {
        "reference_data": [
            {
                "url": "https://xenbits.xenproject.org/xsa/advisory-389.txt",
                "refsource": "MISC",
                "name": "https://xenbits.xenproject.org/xsa/advisory-389.txt"
            },
            {
                "refsource": "FEDORA",
                "name": "FEDORA-2021-03645e9807",
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/I7ZGWVVRI4XY2XSTBI3XEMWBXPDVX6OT/"
            },
            {
                "refsource": "DEBIAN",
                "name": "DSA-5017",
                "url": "https://www.debian.org/security/2021/dsa-5017"
            },
            {
                "refsource": "FEDORA",
                "name": "FEDORA-2021-2b3a2de94f",
                "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PXUI4VMD52CH3T7YXAG3J2JW7ZNN3SXF/"
            }
        ]
    },
    "workaround": {
        "workaround_data": {
            "description": {
                "description_data": [
                    {
                        "lang": "eng",
                        "value": "Not starting x86 HVM or PVH guests in populate-on-demand mode is\nbelieved to allow avoiding the vulnerability."
                    }
                ]
            }
        }
    }
}