{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-50073", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T19:36:19.940Z", "datePublished": "2024-10-29T00:50:15.219Z", "dateUpdated": "2026-08-05T11:41:23.613Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:41:23.613Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\ntty: n_gsm: Fix use-after-free in gsm_cleanup_mux\n\nBUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x77b/0x7b0\ndrivers/tty/n_gsm.c:3160 [n_gsm]\nRead of size 8 at addr ffff88815fe99c00 by task poc/3379\nCPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56\nHardware name: VMware, Inc. VMware Virtual Platform/440BX\nDesktop Reference Platform, BIOS 6.00 11/12/2020\nCall Trace:\n \n gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]\n __pfx_gsm_cleanup_mux+0x10/0x10 drivers/tty/n_gsm.c:3124 [n_gsm]\n __pfx_sched_clock_cpu+0x10/0x10 kernel/sched/clock.c:389\n update_load_avg+0x1c1/0x27b0 kernel/sched/fair.c:4500\n __pfx_min_vruntime_cb_rotate+0x10/0x10 kernel/sched/fair.c:846\n __rb_insert_augmented+0x492/0xbf0 lib/rbtree.c:161\n gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]\n _raw_spin_lock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107\n __pfx_gsmld_ioctl+0x10/0x10 drivers/tty/n_gsm.c:3822 [n_gsm]\n ktime_get+0x5e/0x140 kernel/time/timekeeping.c:195\n ldsem_down_read+0x94/0x4e0 arch/x86/include/asm/atomic64_64.h:79\n __pfx_ldsem_down_read+0x10/0x10 drivers/tty/tty_ldsem.c:338\n __pfx_do_vfs_ioctl+0x10/0x10 fs/ioctl.c:805\n tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818\n\nAllocated by task 65:\n gsm_data_alloc.constprop.0+0x27/0x190 drivers/tty/n_gsm.c:926 [n_gsm]\n gsm_send+0x2c/0x580 drivers/tty/n_gsm.c:819 [n_gsm]\n gsm1_receive+0x547/0xad0 drivers/tty/n_gsm.c:3038 [n_gsm]\n gsmld_receive_buf+0x176/0x280 drivers/tty/n_gsm.c:3609 [n_gsm]\n tty_ldisc_receive_buf+0x101/0x1e0 drivers/tty/tty_buffer.c:391\n tty_port_default_receive_buf+0x61/0xa0 drivers/tty/tty_port.c:39\n flush_to_ldisc+0x1b0/0x750 drivers/tty/tty_buffer.c:445\n process_scheduled_works+0x2b0/0x10d0 kernel/workqueue.c:3229\n worker_thread+0x3dc/0x950 kernel/workqueue.c:3391\n kthread+0x2a3/0x370 kernel/kthread.c:389\n ret_from_fork+0x2d/0x70 arch/x86/kernel/process.c:147\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:257\n\nFreed by task 3367:\n kfree+0x126/0x420 mm/slub.c:4580\n gsm_cleanup_mux+0x36c/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm]\n gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm]\n tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818\n\n[Analysis]\ngsm_msg on the tx_ctrl_list or tx_data_list of gsm_mux\ncan be freed by multi threads through ioctl,which leads\nto the occurrence of uaf. Protect it by gsm tx lock." } ], "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 vulnerability is triggered entirely through local syscalls on a tty file descriptor — `ioctl(TIOCSETD, N_GSM0710)` followed by concurrent `ioctl(GSMIOC_SETCONF)` on a pty the attacker owns. No network or physical access is involved.\nAC:L - The attacker controls both sides of the race — two threads issuing `GSMIOC_SETCONF` on the same fd, which `tty_ldisc_ref_wait()`'s read semaphore explicitly permits to run concurrently — and additionally controls list population by writing to the pty peer to queue `gsm_msg` nodes on demand. No condition depends on attacker-uninfluenceable state.\nPR:L - For mainline v6.0–v6.5 and the never-fixed 5.18.18/5.19.2 stable branches covered by this CVE, `gsmld_open()` has no capability check at all, so any unprivileged local user with a pty reaches the bug; even on kernels carrying the later `capable(CAP_NET_ADMIN)` gate, that is a scoped, non-root-equivalent capability routinely granted to network daemons and containers (`--cap-add=NET_ADMIN`).\nUI:N - The attacker performs every step itself — allocating the pty, attaching the line discipline, feeding data, and racing the two ioctls. No victim action or cooperating process is required.\nS:U - The corruption and its consequences are confined to the kernel of the running system, a standard local privilege-escalation boundary. No hypervisor, IOMMU, or other security-authority boundary is crossed.\nC:H - The unlocked traversal reads `list.next` from a freed, attacker-reclaimable slab object, and the resulting arbitrary-free primitive converts into a use-after-free on a chosen kernel object, enabling arbitrary kernel memory disclosure.\nI:H - Concurrent `kfree()` of the same nodes double-frees them and corrupts the SLUB freelist, while a sprayed `next` pointer yields `kfree()` of an attacker-chosen address — an arbitrary-free primitive that is a well-established path to arbitrary write and control-flow hijack.\nA:H - The double-free and use-after-free reliably corrupt slab metadata, producing kernel oops or panic even in unweaponized form, as demonstrated by the KASAN slab-use-after-free report in the fix commit." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/tty/n_gsm.c" ], "versions": [ { "version": "0af021678d5d30c31f5a6b631f404ead3575212a", "lessThan": "bf171b5e86e41de4c1cf32fb7aefa275c3d7de49", "status": "affected", "versionType": "git" }, { "version": "0af021678d5d30c31f5a6b631f404ead3575212a", "lessThan": "c29f192e0d44cc1cbaf698fa1ff198f63556691a", "status": "affected", "versionType": "git" }, { "version": "0af021678d5d30c31f5a6b631f404ead3575212a", "lessThan": "0eec592c6a7460ba795d7de29f3dc95cb5422e62", "status": "affected", "versionType": "git" }, { "version": "0af021678d5d30c31f5a6b631f404ead3575212a", "lessThan": "9462f4ca56e7d2430fdb6dcc8498244acbfc4489", "status": "affected", "versionType": "git" }, { "version": "5020173e7e7725110a8d4be1359bf1dfc4b1814d", "status": "affected", "versionType": "git" }, { "version": "c165698c9919b000bdbe73859d3bb7b33bdb9223", "status": "affected", "versionType": "git" }, { "version": "7962a4b900099cf90e02859bb297f2c618d8d940", "status": "affected", "versionType": "git" }, { "version": "5.15.209", "lessThan": "5.16", "status": "affected", "versionType": "semver" }, { "version": "5.18.18", "lessThan": "5.19", "status": "affected", "versionType": "semver" }, { "version": "5.19.2", "lessThan": "5.20", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/tty/n_gsm.c" ], "versions": [ { "version": "6.0", "status": "affected" }, { "version": "0", "lessThan": "6.0", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.114", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.58", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.5", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "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": "6.0", "versionEndExcluding": "6.1.114" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.6.58" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.11.5" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.0", "versionEndExcluding": "6.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.15.209" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.18.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.19.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/bf171b5e86e41de4c1cf32fb7aefa275c3d7de49" }, { "url": "https://git.kernel.org/stable/c/c29f192e0d44cc1cbaf698fa1ff198f63556691a" }, { "url": "https://git.kernel.org/stable/c/0eec592c6a7460ba795d7de29f3dc95cb5422e62" }, { "url": "https://git.kernel.org/stable/c/9462f4ca56e7d2430fdb6dcc8498244acbfc4489" } ], "title": "tty: n_gsm: Fix use-after-free in gsm_cleanup_mux", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "scope": "UNCHANGED", "version": "3.1", "baseScore": 7.8, "attackVector": "LOCAL", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2024-50073", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2024-12-11T14:26:06.514773Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "cweId": "CWE-416", "description": "CWE-416 Use After Free" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-12-11T14:58:34.728Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:25:08.310Z" } } ] } }