{ "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" } } } }