{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-72379",
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "state": "PUBLISHED",
        "assignerShortName": "Linux",
        "dateReserved": "2026-08-09T03:40:39.922Z",
        "datePublished": "2026-08-15T05:56:12.251Z",
        "dateUpdated": "2026-08-17T05:13:31.893Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
                "shortName": "Linux",
                "dateUpdated": "2026-08-17T05:13:31.893Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: refuse O_TMPFILE creation with an unmapped fsuid or fsgid\n\nvfs_tmpfile() never checked that the caller's fsuid and fsgid map into\nthe filesystem.  On an idmapped mount whose idmapping does not cover the\ncaller's fs{u,g}id, the ->tmpfile() instance initializes the new inode\nthrough inode_init_owner(), where mapped_fsuid()/mapped_fsgid() return\nINVALID_UID/INVALID_GID, and the tmpfile ends up owned by (uid_t)-1.\n\nEvery other creation path already refuses this: may_o_create() (O_CREAT)\nand may_create_dentry() (mkdir, mknod, symlink, link) bail out with\n-EOVERFLOW via fsuidgid_has_mapping() precisely so that an object cannot\nbe created with an owner the filesystem cannot represent.  An O_TMPFILE\nis no exception: it is created I_LINKABLE and linkat(2) can splice it\ninto the namespace afterwards, so the same guarantee must hold.\n\nAdd the missing fsuidgid_has_mapping() check to vfs_tmpfile().  On a\nnon-idmapped mount the caller's fs{u,g}id always map in the superblock's\nuser namespace, so this is a no-op there and only takes effect on an\nidmapped mount that does not map the caller.  It applies to every\nfilesystem that sets FS_ALLOW_IDMAP and implements ->tmpfile() (tmpfs,\next4, btrfs, xfs, f2fs, ...), and to overlayfs, whose upper-layer\ntmpfile creation funnels through vfs_tmpfile() via backing_tmpfile_open()."
                }
            ],
            "affected": [
                {
                    "product": "Linux",
                    "vendor": "Linux",
                    "defaultStatus": "unaffected",
                    "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                    "programFiles": [
                        "fs/namei.c"
                    ],
                    "versions": [
                        {
                            "version": "8e5389132ab429604c1a2459b52f0c849a71cc61",
                            "lessThan": "bac8fb0d60254846f3b56957435dcd870ae12948",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8e5389132ab429604c1a2459b52f0c849a71cc61",
                            "lessThan": "503d0568a525b168d9aa5ca046ec72fc5477df84",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8e5389132ab429604c1a2459b52f0c849a71cc61",
                            "lessThan": "a2038514e69371eb493083a6a897ed20fcbb8acb",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8e5389132ab429604c1a2459b52f0c849a71cc61",
                            "lessThan": "47e434da476b5a8bcd1e6e52ab03c5ee7764ee78",
                            "status": "affected",
                            "versionType": "git"
                        },
                        {
                            "version": "8e5389132ab429604c1a2459b52f0c849a71cc61",
                            "lessThan": "539dce1144651f7976fa418e618b0b574bf15eeb",
                            "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/namei.c"
                    ],
                    "versions": [
                        {
                            "version": "5.13",
                            "status": "affected"
                        },
                        {
                            "version": "0",
                            "lessThan": "5.13",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.6.145",
                            "lessThanOrEqual": "6.6.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.12.97",
                            "lessThanOrEqual": "6.12.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "6.18.40",
                            "lessThanOrEqual": "6.18.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.1.5",
                            "lessThanOrEqual": "7.1.*",
                            "status": "unaffected",
                            "versionType": "semver"
                        },
                        {
                            "version": "7.2",
                            "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": "5.13",
                                    "versionEndExcluding": "6.6.145"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.13",
                                    "versionEndExcluding": "6.12.97"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.13",
                                    "versionEndExcluding": "6.18.40"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.13",
                                    "versionEndExcluding": "7.1.5"
                                },
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                                    "versionStartIncluding": "5.13",
                                    "versionEndExcluding": "7.2"
                                }
                            ]
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://git.kernel.org/stable/c/bac8fb0d60254846f3b56957435dcd870ae12948"
                },
                {
                    "url": "https://git.kernel.org/stable/c/503d0568a525b168d9aa5ca046ec72fc5477df84"
                },
                {
                    "url": "https://git.kernel.org/stable/c/a2038514e69371eb493083a6a897ed20fcbb8acb"
                },
                {
                    "url": "https://git.kernel.org/stable/c/47e434da476b5a8bcd1e6e52ab03c5ee7764ee78"
                },
                {
                    "url": "https://git.kernel.org/stable/c/539dce1144651f7976fa418e618b0b574bf15eeb"
                }
            ],
            "title": "fs: refuse O_TMPFILE creation with an unmapped fsuid or fsgid",
            "x_generator": {
                "engine": "bippy-1.2.0"
            }
        }
    }
}