procfs: fix missing RCU protection when reading real_parent in do_task_stat()_CVE-2026-46259

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nprocfs: fix missing RCU protection when reading real_parent in do_task_stat()\n\nWhen reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent\nwithout proper RCU protection, which leads to:\n\n  cpu 0                               cpu 1\n  -----                               -----\n  do_task_stat\n    var = task->real_parent\n                                      release_task\n                                        call_rcu(delayed_put_task_struct)\n    task_tgid_nr_ns(var)\n      rcu_read_lock   <--- Too late to protect task->real_parent!\n      task_pid_ptr    <--- UAF!\n      rcu_read_unlock\n\nThis patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add\nproper RCU protection for accessing task->real_parent.",
    "published": "2026-06-03T15:49:56.428Z",
    "modified": "2026-06-05T06:06:27.857Z",
    "type": "cve",
    "title": "procfs: fix missing RCU protection when reading real_parent in do_task_stat()",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/fefa0fcd78be465b7ad4c497fa6ec90d64194c04\nhttps://git.kernel.org/stable/c/c93a33f28f915d446eea6fb3f0e1def0b3af1982\nhttps://git.kernel.org/stable/c/1c8dc5b5517546c68ffae40b948336122bb61306\nhttps://git.kernel.org/stable/c/0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e\nhttps://git.kernel.org/stable/c/73ec7c96601d61d52310c659145bb06d933a0fa6\nhttps://git.kernel.org/stable/c/4f9ae386861e280b7631ca252f798d25575627ee\nhttps://git.kernel.org/stable/c/dd8b13cb4ff1a4545a214ed897fdf2bc341155b6\nhttps://git.kernel.org/stable/c/76149d53502cf17ef3ae454ff384551236fba867",
    "id": "CVE-2026-46259",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 06fffb1267c9d986687b69d74a46ee332a50575e\nLinux Linux 2.6.26",
    "sourceHref": "",
    "cvss": {
        "score": 7.8,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
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        "baseScore": 0,
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        "privilegesRequired": "",
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        "scope": "",
        "confidentialityImpact": "",
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        "cvssV3": {
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    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "06fffb1267c9d986687b69d74a46ee332a50575e",
    "vendor": "Linux",
    "ai_description": "",
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    "ai_score": 0
}