{
    "id": "CVE-2019-15791",
    "published": "2020-04-24 00:15:11",
    "last_modified": "2026-06-17 02:21:04",
    "cvss_score": "7.1",
    "cvss_severity": "HIGH",
    "cvss_version": "3.1",
    "cvss_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H",
    "cwe": "CWE-672",
    "description": "In shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, shiftfs_btrfs_ioctl_fd_replace() installs an fd referencing a file from the lower filesystem without taking an additional reference to that file. After the btrfs ioctl completes this fd is closed, which then puts a reference to that file, leading to a refcount underflow.",
    "epss_score": "0.01317",
    "epss_percentile": "0.69984",
    "kev": 0,
    "kev_due": null,
    "has_exploit": 1,
    "updated_at": "2026-10-11 18:17:20",
    "priority": {
        "rank": 2,
        "label": "Patch early",
        "why": "A public exploit exists."
    },
    "products": [
        {
            "vendor": "canonical",
            "product": "ubuntu_linux"
        },
        {
            "vendor": "linux",
            "product": "linux_kernel"
        }
    ],
    "kev_detail": null,
    "exploits": [
        {
            "source": "exploit-db",
            "ref_id": "47693",
            "title": "Ubuntu 19.10 - Refcount Underflow and Type Confusion in shiftfs",
            "date": "2019-11-20",
            "url": "https://www.exploit-db.com/exploits/47693"
        }
    ],
    "refs_list": [
        "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=601a64857b3d7040ca15c39c929e6b9db3373ec1",
        "https://usn.ubuntu.com/usn/usn-4183-1",
        "https://usn.ubuntu.com/usn/usn-4184-1",
        "https://git.launchpad.net/~ubuntu-kernel/ubuntu/+source/linux/+git/eoan/commit/?id=601a64857b3d7040ca15c39c929e6b9db3373ec1",
        "https://usn.ubuntu.com/usn/usn-4183-1",
        "https://usn.ubuntu.com/usn/usn-4184-1"
    ]
}