{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-63990",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-07-19T07:54:57.025Z",
        "datePublished": "2026-07-19T14:56:11.111Z",
        "dateUpdated": "2026-07-19T14:56:11.111Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-07-19T14:56:11.111Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbonding: refuse to enslave CAN devices\n\nsyzbot reported a kernel paging request crash in\ncan_rx_unregister() inside net/can/af_can.c. The crash occurs\nbecause a virtual CAN device (vxcan) is being enslaved to a\nbonding master.\n\nDuring the enslavement process, the bonding driver mutates\nand modifies the network device states to fit an Ethernet-like\naggregation model. However, CAN devices operate on a completely\ndifferent Layer 2 architecture, relying on the CAN mid-layer\nprivate data structure (can_ml_priv) instead of standard\nEthernet structures. Since bonding does not initialize or\nmaintain these CAN structures, subsequent operations on the\nhalf-enslaved interface (such as closing associated sockets\nvia isotp_release) lead to a null-pointer dereference when\naccessing the CAN receiver lists.\n\nBonding CAN interfaces is architecturally invalid as CAN lacks\nMAC addresses, ARP capabilities, and standard Ethernet\nlink-layer mechanisms. While generic loopback devices are\nblocked globally in net/core/dev.c, virtual CAN devices\nbypass this check because they do not carry the IFF_LOOPBACK\nflag, despite acting as local software-loopbacks.\n\nFix this by explicitly blocking network devices of type\nARPHRD_CAN from being enslaved at the very beginning of\nbond_enslave(). This prevents illegal state mutations,\neliminates the resulting KASAN crashes, and avoids potential\nmemory leaks from incomplete socket cleanups.\n\nAs the CAN support has been added a long time after bonding\nthe Fixes-tag points to the introduction of ARPHRD_CAN that\nwould have needed a specific handling in bonding_main.c."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/bonding/bond_main.c"
                    ],
                    "versions": [
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "69b78b5f3033272e53a2dc2dad675962654a5b38",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "41e8478c4cd896d3abbe33d41afc90c84ac66602",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "f4d78a81f57df82e9d82a2c07471fed1a1235893",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "02f1c87ded33b43d48b4a1d665da15f2157b30d8",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "9ea8a648d9120f7652bcde1ce2c4ad66871af707",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "563090e5d450c665f70d955a39f9587afc7842eb",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "cd05acfe65ed2cf2db683fa9a6adb8d35635263b",
                            "lessThan": "8ba68464e4787b6a7ec938826e16124df20fd23d",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "drivers/net/bonding/bond_main.c"
                    ],
                    "versions": [
                        {
                            "version": "2.6.25",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "2.6.25",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.210",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.176",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.143",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.93",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.35",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0.12",
                            "lessThanOrEqual": "7.0.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "5.15.210"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "6.1.176"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "6.6.143"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "6.12.93"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "6.18.35"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "7.0.12"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "2.6.25",
                                    "versionEndExcluding": "7.1"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/69b78b5f3033272e53a2dc2dad675962654a5b38"
                },
                {
                    "url": "https://git.kernel.org/stable/c/41e8478c4cd896d3abbe33d41afc90c84ac66602"
                },
                {
                    "url": "https://git.kernel.org/stable/c/f4d78a81f57df82e9d82a2c07471fed1a1235893"
                },
                {
                    "url": "https://git.kernel.org/stable/c/02f1c87ded33b43d48b4a1d665da15f2157b30d8"
                },
                {
                    "url": "https://git.kernel.org/stable/c/9ea8a648d9120f7652bcde1ce2c4ad66871af707"
                },
                {
                    "url": "https://git.kernel.org/stable/c/563090e5d450c665f70d955a39f9587afc7842eb"
                },
                {
                    "url": "https://git.kernel.org/stable/c/8ba68464e4787b6a7ec938826e16124df20fd23d"
                }
            ],
            "title": "bonding: refuse to enslave CAN devices",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}