{
    "CVE_data_meta": {
        "ASSIGNER": "security@ubuntu.com",
        "DATE_PUBLIC": "2021-03-23T00:00:00.000Z",
        "ID": "CVE-2021-3444",
        "STATE": "PUBLIC",
        "TITLE": "Linux kernel bpf verifier incorrect mod32 truncation"
    },
    "affects": {
        "vendor": {
            "vendor_data": [
                {
                    "product": {
                        "product_data": [
                            {
                                "product_name": "kernel",
                                "version": {
                                    "version_data": [
                                        {
                                            "version_affected": "<",
                                            "version_name": "trunk",
                                            "version_value": "5.12-rc1"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "5.11",
                                            "version_value": "5.11.2"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "5.10",
                                            "version_value": "5.10.19"
                                        },
                                        {
                                            "version_affected": "<",
                                            "version_name": "5.4",
                                            "version_value": "5.4.101"
                                        }
                                    ]
                                }
                            }
                        ]
                    },
                    "vendor_name": "Linux"
                }
            ]
        }
    },
    "credit": [
        {
            "lang": "eng",
            "value": "De4dCr0w of 360 Alpha Lab"
        }
    ],
    "data_format": "MITRE",
    "data_type": "CVE",
    "data_version": "4.0",
    "description": {
        "description_data": [
            {
                "lang": "eng",
                "value": "The bpf verifier in the Linux kernel did not properly handle mod32 destination register truncation when the source register was known to be 0. A local attacker with the ability to load bpf programs could use this gain out-of-bounds reads in kernel memory leading to information disclosure (kernel memory), and possibly out-of-bounds writes that could potentially lead to code execution. This issue was addressed in the upstream kernel in commit 9b00f1b78809 (\"bpf: Fix truncation handling for mod32 dst reg wrt zero\") and in Linux stable kernels 5.11.2, 5.10.19, and 5.4.101."
            }
        ]
    },
    "generator": {
        "engine": "Vulnogram 0.0.9"
    },
    "impact": {
        "cvss": {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H",
            "version": "3.1"
        }
    },
    "problemtype": {
        "problemtype_data": [
            {
                "description": [
                    {
                        "lang": "eng",
                        "value": "CWE-681: Incorrect Conversion between Numeric Types"
                    }
                ]
            }
        ]
    },
    "references": {
        "reference_data": [
            {
                "refsource": "MISC",
                "url": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9b00f1b78809",
                "name": "https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9b00f1b78809"
            },
            {
                "refsource": "MISC",
                "url": "https://www.openwall.com/lists/oss-security/2021/03/23/2",
                "name": "https://www.openwall.com/lists/oss-security/2021/03/23/2"
            },
            {
                "refsource": "MLIST",
                "name": "[oss-security] 20210323 [CVE-2021-3444] Linux kernel bpf verifier incorrect mod32 truncation",
                "url": "http://www.openwall.com/lists/oss-security/2021/03/23/2"
            },
            {
                "refsource": "MISC",
                "name": "http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html",
                "url": "http://packetstormsecurity.com/files/162117/Kernel-Live-Patch-Security-Notice-LSN-0075-1.html"
            },
            {
                "refsource": "CONFIRM",
                "name": "https://security.netapp.com/advisory/ntap-20210416-0006/",
                "url": "https://security.netapp.com/advisory/ntap-20210416-0006/"
            },
            {
                "refsource": "MLIST",
                "name": "[debian-lts-announce] 20211015 [SECURITY] [DLA 2785-1] linux-4.19 security update",
                "url": "https://lists.debian.org/debian-lts-announce/2021/10/msg00010.html"
            },
            {
                "refsource": "MISC",
                "name": "http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html",
                "url": "http://packetstormsecurity.com/files/164950/Kernel-Live-Patch-Security-Notice-LSN-0082-1.html"
            }
        ]
    },
    "solution": [
        {
            "lang": "eng",
            "value": "Apply or update to a kernel that contains the commit 9b00f1b78809 (\"bpf: Fix truncation handling for mod32 dst reg wrt zero\")."
        }
    ],
    "source": {
        "discovery": "EXTERNAL"
    }
}