{"id":"CVE-2021-47358","state":"PUBLISHED","title":"staging: greybus: uart: fix tty use after free","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: greybus: uart: fix tty use after free\n\nUser space can hold a tty open indefinitely and tty drivers must not\nrelease the underlying structures until the last user is gone.\n\nSwitch to using the tty-port reference counter to manage the life time\nof the greybus tty state to avoid use after free after a disconnect.","publishedAt":"2024-05-21T14:44:50.221Z","updatedAt":"2026-08-05T08:47:27.000Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux 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memory.\nI:H - UAF of a structure embedding tty_port ops enables heap spray and hijacking of function pointers on subsequent close/write paths for arbitrary write/code execution.\nA:H - Dereferencing the freed gb_tty on close, write, or cleanup causes kernel oops/panic even without full 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