{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-43106",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-05-01T14:12:55.986Z",
        "datePublished": "2026-05-06T07:40:34.365Z",
        "dateUpdated": "2026-08-05T12:25:56.425Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-05T12:25:56.425Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ncachefiles: fix incorrect dentry refcount in cachefiles_cull()\n\nThe patch mentioned below changed cachefiles_bury_object() to expect 2\nreferences to the 'rep' dentry.  Three of the callers were changed to\nuse start_removing_dentry() which takes an extra reference so in those\ncases the call gets the expected references.\n\nHowever there is another call to cachefiles_bury_object() in\ncachefiles_cull() which did not need to be changed to use\nstart_removing_dentry() and so was not properly considered.\nIt still passed the dentry with just one reference so the net result is\nthat a reference is lost.\n\nTo meet the expectations of cachefiles_bury_object(), cachefiles_cull()\nmust take an extra reference before the call.  It will be dropped by\ncachefiles_bury_object()."
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                        "baseScore": 7.8,
                        "baseSeverity": "HIGH"
                    },
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "AV:L - The vulnerable path is reached through local CacheFiles/cachefilesd activity and the `/dev/cachefiles` control interface, not by directly processing remote packets.\nAC:L - The refcount bug is deterministic once a cull operation reaches `cachefiles_cull()`; there is no attacker-uncontrolled race required, and cache pressure/cullable objects can be induced in a normal CacheFiles-backed deployment.\nPR:L - Directly opening `/dev/cachefiles` requires init-namespace `CAP_SYS_ADMIN`, but culling is normally performed by the privileged cachefilesd daemon in response to cache pressure. A local unprivileged user with access to a CacheFiles-backed mount can plausibly create cache pressure and cullable objects that cause the daemon to trigger the vulnerable command.\nUI:N - No victim user action is required once the attacker can generate the local cache activity; cachefilesd culling is daemon-driven.\nS:U - The vulnerability corrupts kernel/VFS state within the same operating-system security authority and does not cross a VM, IOMMU, or similar boundary.\nC:H - The missing extra dentry reference can produce a use-after-free/double-put on a kernel dentry. Under the required kernel guidance, UAF memory corruption is scored as capable of high confidentiality impact.\nI:H - The freed dentry can be reused while still dereferenced or put again, making this kernel memory corruption. Under the required guidance, UAFs are treated as potentially enabling arbitrary write/control-flow impact.\nA:H - The dentry refcount loss can lead to use-after-free, refcount underflow, or invalid dput paths in the kernel. Such corruption can reliably crash or oops the kernel, so availability impact is high."
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/cachefiles/namei.c"
                    ],
                    "versions": [
                        {
                            "version": "7bb1eb45e43c4730cbc5a48b9e9295049fccdacb",
                            "lessThan": "6577df7dc7a7de128442b6192c7a32195c923480",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "7bb1eb45e43c4730cbc5a48b9e9295049fccdacb",
                            "lessThan": "1635c2acdde86c4f555b627aec873c8677c421ed",
                            "status": "affected",
                            "versionType": "git"
                        }
                    ]
                },
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "affected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/cachefiles/namei.c"
                    ],
                    "versions": [
                        {
                            "version": "6.19",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "6.19",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.19.14",
                            "lessThanOrEqual": "6.19.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.0",
                            "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": "6.19",
                                    "versionEndExcluding": "6.19.14"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "6.19",
                                    "versionEndExcluding": "7.0"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/6577df7dc7a7de128442b6192c7a32195c923480"
                },
                {
                    "url": "https://git.kernel.org/stable/c/1635c2acdde86c4f555b627aec873c8677c421ed"
                }
            ],
            "title": "cachefiles: fix incorrect dentry refcount in cachefiles_cull()",
            "x_generator": {
                "engine": "bippy-1.2.0"
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        }
    }
}