{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2023-54198","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2025-12-30T12:06:44.499Z","datePublished":"2025-12-30T12:09:04.229Z","dateUpdated":"2026-08-05T09:17:57.447Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T09:17:57.447Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\ntty: fix out-of-bounds access in tty_driver_lookup_tty()\n\nWhen specifying an invalid console= device like console=tty3270,\ntty_driver_lookup_tty() returns the tty struct without checking\nwhether index is a valid number.\n\nTo reproduce:\n\nqemu-system-x86_64 -enable-kvm -nographic -serial mon:stdio \\\n-kernel ../linux-build-x86/arch/x86/boot/bzImage \\\n-append \"console=ttyS0 console=tty3270\"\n\nThis crashes with:\n\n[    0.770599] BUG: kernel NULL pointer dereference, address: 00000000000000ef\n[    0.771265] #PF: supervisor read access in kernel mode\n[    0.771773] #PF: error_code(0x0000) - not-present page\n[    0.772609] Oops: 0000 [#1] PREEMPT SMP PTI\n[    0.774878] RIP: 0010:tty_open+0x268/0x6f0\n[    0.784013]  chrdev_open+0xbd/0x230\n[    0.784444]  ? cdev_device_add+0x80/0x80\n[    0.784920]  do_dentry_open+0x1e0/0x410\n[    0.785389]  path_openat+0xca9/0x1050\n[    0.785813]  do_filp_open+0xaa/0x150\n[    0.786240]  file_open_name+0x133/0x1b0\n[    0.786746]  filp_open+0x27/0x50\n[    0.787244]  console_on_rootfs+0x14/0x4d\n[    0.787800]  kernel_init_freeable+0x1e4/0x20d\n[    0.788383]  ? rest_init+0xc0/0xc0\n[    0.788881]  kernel_init+0x11/0x120\n[    0.789356]  ret_from_fork+0x22/0x30"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The out-of-bounds access is reached through a local `open()` syscall on the console character device (`tty_open` → `tty_open_by_driver` → `tty_driver_lookup_tty`); no network or physical interaction is part of the trigger itself.\nAC:L - On an affected system the OOB read fires deterministically on every open of the console device — no race, no timing window, and it is freely repeatable, which also lets an unprivileged process groom the adjacent slab objects that the read lands in.\nPR:L - Reaching the code needs only an open() of the console device, which on the plausible worst-case deployments (embedded/appliance and container images that expose /dev/console to non-root, busybox-style rootfs) is available to an ordinary local user; heap grooming to shape the wild pointer likewise needs no privilege.\nUI:N - No victim action is required — the attacker's own open() triggers the access, and on the reported path `console_on_rootfs()` hits it automatically during kernel init.\nS:U - The out-of-bounds read, the wild-pointer dereference and the refcount write all occur inside the kernel's own security authority; no VM, IOMMU or sandbox boundary is crossed.\nC:H - The read is an unbounded out-of-bounds fetch (index up to INT_MAX elements past a 63-entry array), and the value is then treated as a `struct tty_struct *` whose termios/ldisc/driver fields are dereferenced and exposed through the resulting tty file, giving arbitrary kernel-memory disclosure rather than a bounded few-byte leak.\nI:H - The garbage pointer is passed to `tty_kref_get()` → `refcount_inc()`, a read-modify-write at an attacker-influenced kernel address, followed by further writes in `tty_lock_interruptible()` and `tty_reopen()` (`tty->count++`, ldisc state) — a memory-corruption primitive usable for control-flow hijacking.\nA:H - The commit documents a kernel NULL-pointer dereference and Oops in `tty_open+0x268/0x6f0`; the wild-pointer dereference reliably panics the kernel, and on the boot path it prevents the system from coming up at all."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/tty_io.c"],"versions":[{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"3df6f492f500a16c231f07ccc6f6ed1302caddf9","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"b79109d6470aaae7062998353e3a19449055829d","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"953a4a352a0c185460ae1449e4c6e6658e55fdfc","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"84ea44dc3e4ecb2632586238014bf6722aa5843b","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"f9d9d25ad1f0d060eaf297a2f7f03b5855a45561","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"765566110eb0da3cf60198b0165ecceeaafa6444","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"fcfeaa570f7a5c2d5f4f14931909531ff18b7fde","status":"affected","versionType":"git"},{"version":"99f1fe189daf8e99a847e420567e49dd7ee2aae7","lessThan":"db4df8e9d79e7d37732c1a1b560958e8dadfefa1","status":"affected","versionType":"git"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/tty/tty_io.c"],"versions":[{"version":"2.6.28","status":"affected"},{"version":"0","lessThan":"2.6.28","status":"unaffected","versionType":"semver"},{"version":"4.14.308","lessThanOrEqual":"4.14.*","status":"unaffected","versionType":"semver"},{"version":"4.19.276","lessThanOrEqual":"4.19.*","status":"unaffected","versionType":"semver"},{"version":"5.4.235","lessThanOrEqual":"5.4.*","status":"unaffected","versionType":"semver"},{"version":"5.10.173","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.100","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.18","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.2.5","lessThanOrEqual":"6.2.*","status":"unaffected","versionType":"semver"},{"version":"6.3","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":"2.6.28","versionEndExcluding":"4.14.308"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"4.19.276"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"5.4.235"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"5.10.173"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"5.15.100"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"6.1.18"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"6.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.28","versionEndExcluding":"6.3"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/3df6f492f500a16c231f07ccc6f6ed1302caddf9"},{"url":"https://git.kernel.org/stable/c/b79109d6470aaae7062998353e3a19449055829d"},{"url":"https://git.kernel.org/stable/c/953a4a352a0c185460ae1449e4c6e6658e55fdfc"},{"url":"https://git.kernel.org/stable/c/84ea44dc3e4ecb2632586238014bf6722aa5843b"},{"url":"https://git.kernel.org/stable/c/f9d9d25ad1f0d060eaf297a2f7f03b5855a45561"},{"url":"https://git.kernel.org/stable/c/765566110eb0da3cf60198b0165ecceeaafa6444"},{"url":"https://git.kernel.org/stable/c/fcfeaa570f7a5c2d5f4f14931909531ff18b7fde"},{"url":"https://git.kernel.org/stable/c/db4df8e9d79e7d37732c1a1b560958e8dadfefa1"}],"title":"tty: fix out-of-bounds access in tty_driver_lookup_tty()","x_generator":{"engine":"bippy-1.2.0"}}}}