libceph: Fix potential null-ptr-deref in decode_choose_args()_CVE-2026-52957

{
    "lastseen": "",
    "description": "In the Linux kernel, the following vulnerability has been resolved:\n\nlibceph: Fix potential null-ptr-deref in decode_choose_args()\n\nA message of type CEPH_MSG_OSD_MAP contains an OSD map that itself\ncontains a CRUSH map. When decoding this CRUSH map in crush_decode(), an\narray of max_buckets CRUSH buckets is decoded, where some indices may\nnot refer to actual buckets and are therefore set to NULL. The received\nCRUSH map may optionally contain choose_args that get decoded in\ndecode_choose_args(). When decoding a crush_choose_arg_map, a series of\nchoose_args for different buckets is decoded, with the bucket_index\nbeing read from the incoming message. It is only checked that the bucket\nindex does not exceed max_buckets, but not that it doesn't point to an\nindex with a NULL bucket. If a (potentially corrupted) message contains\na crush_choose_arg_map including such a bucket_index, a null pointer\ndereference may occur in the subsequent processing when attempting to\naccess the bucket with the given index.\n\nThis patch fixes the issue by extending the affected check. Now, it is\nonly attempted to access the bucket if it is not NULL.",
    "published": "2026-06-24T16:28:39.066Z",
    "modified": "2026-06-28T06:37:17.986Z",
    "type": "cve",
    "title": "libceph: Fix potential null-ptr-deref in decode_choose_args()",
    "source": "Linux",
    "references": "https://git.kernel.org/stable/c/d55ffad8d422b5d1cc44dad32bd3d25f4471cd9f\nhttps://git.kernel.org/stable/c/301286c0ccd37d66b0e40786fd35a4f19cdbd88a\nhttps://git.kernel.org/stable/c/7169f326a23d0f547fcd90e68b72fd387622e126\nhttps://git.kernel.org/stable/c/d7a65a34d2453f8cd3e0cc0e1319740af7e24276\nhttps://git.kernel.org/stable/c/312ec973efac0efb9b9ed64214235910e9ecbaa8\nhttps://git.kernel.org/stable/c/f2f95e6d4b97e70bb876139b0583fc8079983f85\nhttps://git.kernel.org/stable/c/a20e16ebfe2fa65348eb4b2dc7deac330ce03e9c\nhttps://git.kernel.org/stable/c/28b0a2ab8c82d0bbdeb8013029c67c978ce6e4bf",
    "id": "CVE-2026-52957",
    "bulletinFamily": "",
    "cwe": null,
    "cvelist": null,
    "sourceData": "Linux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2\nLinux Linux 0\nLinux Linux 0\nLinux Linux 0\nLinux Linux 0\nLinux Linux 0\nLinux Linux 0\nLinux Linux 0",
    "sourceHref": "",
    "cvss": {
        "score": 7.5,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
        "version": "3.1"
    },
    "cvss2": [],
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        "baseScore": 0,
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    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Linux",
    "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
    "vendor": "Linux",
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    "ai_score": 0
}