{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-43134",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-05-01T14:12:55.988Z",
        "datePublished": "2026-05-06T11:27:21.541Z",
        "dateUpdated": "2026-08-05T12:26:10.307Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:26:10.307Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nBluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ\n\nThis adds a check for encryption key size upon receiving\nL2CAP_LE_CONN_REQ which is required by L2CAP/LE/CFC/BV-15-C which\nexpects L2CAP_CR_LE_BAD_KEY_SIZE."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
                        "baseScore": 8.1,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:A - The vulnerable request is an incoming Bluetooth LE L2CAP signaling packet from a nearby Bluetooth peer, so exploitation requires adjacent radio proximity rather than IP network or local shell access.\nAC:L - An attacker who can establish an LE link can send an L2CAP_LE_CONN_REQ with an insufficient encryption key size and reliably reach the missing check; there is no race or condition outside attacker control.\nPR:N - The attacker does not need privileges on the target system; Bluetooth pairing/encryption is a protocol precondition, not an OS privilege, and the vulnerable authorization decision is made from received peer traffic.\nUI:N - In a reasonable deployment with a listening LE L2CAP service and connectable device, exploitation is triggered by the adjacent peer’s protocol messages without requiring the victim to open a file, mount anything, or perform an action.\nS:U - The issue bypasses Bluetooth/L2CAP security policy within the same kernel and host Bluetooth service security authority, with no VM, sandbox, or hardware boundary escape.\nC:H - Accepting a channel despite an insufficient encryption key can expose all data carried by a protected LE Credit Based L2CAP service; for high-impact Bluetooth deployments, that can disclose sensitive application or device-control data.\nI:H - The same security bypass can allow an adjacent peer using inadequate encryption strength to send commands or modify state over a service that should have rejected the connection, giving high integrity impact in the protected service context.\nA:N - The bug is a missing key-size enforcement check and does not indicate memory corruption, panic, deadlock, resource exhaustion, or another availability failure."
                        }
                    ]
                }
            ],
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                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
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                        "net/bluetooth/l2cap_core.c"
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                            "status": "affected",
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                            "lessThan": "9118601ff90b79e8df3c0c98f48ae00c1b02ecef",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "27e2d4c8d28be1d1b4ecfbffab572d7dbd35254d",
                            "lessThan": "481ea39b342c347b6ac029f3d418486280be4e45",
                            "status": "affected",
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                            "lessThan": "ec91078e132179b04e0c3906b599816c056ceaad",
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                        {
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                            "lessThan": "138d7eca445ef37a0333425d269ee59900ca1104",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "net/bluetooth/l2cap_core.c"
                    ],
                    "versions": [
                        {
                            "version": "3.14",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "3.14",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.10.252",
                            "lessThanOrEqual": "5.10.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "5.15.202",
                            "lessThanOrEqual": "5.15.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.1.165",
                            "lessThanOrEqual": "6.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.128",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.75",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.16",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.6",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "lessThanOrEqual": "*",
                            "status": "unaffected",
                            "versionType": "original_commit_for_fix"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
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                    "nodes": [
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                            "negate": false,
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            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/335071c0c3637064ec250481f589075db44fe4e6"
                },
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                    "url": "https://git.kernel.org/stable/c/fa6ad76fa8623c0a50d529cd5726fa5d819a3be4"
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                    "url": "https://git.kernel.org/stable/c/9118601ff90b79e8df3c0c98f48ae00c1b02ecef"
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                },
                {
                    "url": "https://git.kernel.org/stable/c/138d7eca445ef37a0333425d269ee59900ca1104"
                }
            ],
            "title": "Bluetooth: L2CAP: Fix missing key size check for L2CAP_LE_CONN_REQ",
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