tty: n_gsm: Fix use-after-free in gsm_cleanup_mux (CVE-2024-50073) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2024-50073

tty: n_gsm: Fix use-after-free in gsm_cleanup_mux

Answer in brief

CVE-2024-50073 records a Unknown severity vulnerability in tty: n_gsm: Fix use-after-free in gsm_cleanup_mux. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Oct 29, 2024Updated Aug 5, 2026Source checked Sep 20, 2026First seen by HOL Aug 5, 2026Material review Aug 5, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Linux/Linuxgeneric	>=0af021678d5d30c31f5a6b631f404ead3575212a <bf171b5e86e41de4c1cf32fb7aefa275c3d7de49 \|\| >=0af021678d5d30c31f5a6b631f404ead3575212a <c29f192e0d44cc1cbaf698fa1ff198f63556691a \|\| >=0af021678d5d30c31f5a6b631f404ead3575212a <0eec592c6a7460ba795d7de29f3dc95cb5422e62 \|\| >=0af021678d5d30c31f5a6b631f404ead3575212a <9462f4ca56e7d2430fdb6dcc8498244acbfc4489 \|\| 5020173e7e7725110a8d4be1359bf1dfc4b1814d \|\| c165698c9919b000bdbe73859d3bb7b33bdb9223 \|\| 7962a4b900099cf90e02859bb297f2c618d8d940 \|\| >=5.15.209 <5.16 \|\| >=5.18.18 <5.19 \|\| >=5.19.2 <5.20	bf171b5e86e41de4c1cf32fb7aefa275c3d7de49, c29f192e0d44cc1cbaf698fa1ff198f63556691a, 0eec592c6a7460ba795d7de29f3dc95cb5422e62, 9462f4ca56e7d2430fdb6dcc8498244acbfc4489, 5.16, 5.19, 5.20
Linux/Linuxgeneric	6.0	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Linux/Linux, Linux/Linux.
Review the reported fix. Update Linux/Linux to bf171b5e86e41de4c1cf32fb7aefa275c3d7de49 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Oct 29, 2024
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 5, 2026

Sources and claim methodology

Upstream source description

In the Linux kernel, the following vulnerability has been resolved: tty: n_gsm: Fix use-after-free in gsm_cleanup_mux BUG: KASAN: slab-use-after-free in gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm] Read of size 8 at addr ffff88815fe99c00 by task poc/3379 CPU: 0 UID: 0 PID: 3379 Comm: poc Not tainted 6.11.0+ #56 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 Call Trace: <TASK> gsm_cleanup_mux+0x77b/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm] __pfx_gsm_cleanup_mux+0x10/0x10 drivers/tty/n_gsm.c:3124 [n_gsm] __pfx_sched_clock_cpu+0x10/0x10 kernel/sched/clock.c:389 update_load_avg+0x1c1/0x27b0 kernel/sched/fair.c:4500 __pfx_min_vruntime_cb_rotate+0x10/0x10 kernel/sched/fair.c:846 __rb_insert_augmented+0x492/0xbf0 lib/rbtree.c:161 gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm] _raw_spin_lock_irqsave+0x92/0xf0 arch/x86/include/asm/atomic.h:107 __pfx_gsmld_ioctl+0x10/0x10 drivers/tty/n_gsm.c:3822 [n_gsm] ktime_get+0x5e/0x140 kernel/time/timekeeping.c:195 ldsem_down_read+0x94/0x4e0 arch/x86/include/asm/atomic64_64.h:79 __pfx_ldsem_down_read+0x10/0x10 drivers/tty/tty_ldsem.c:338 __pfx_do_vfs_ioctl+0x10/0x10 fs/ioctl.c:805 tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818 Allocated by task 65: gsm_data_alloc.constprop.0+0x27/0x190 drivers/tty/n_gsm.c:926 [n_gsm] gsm_send+0x2c/0x580 drivers/tty/n_gsm.c:819 [n_gsm] gsm1_receive+0x547/0xad0 drivers/tty/n_gsm.c:3038 [n_gsm] gsmld_receive_buf+0x176/0x280 drivers/tty/n_gsm.c:3609 [n_gsm] tty_ldisc_receive_buf+0x101/0x1e0 drivers/tty/tty_buffer.c:391 tty_port_default_receive_buf+0x61/0xa0 drivers/tty/tty_port.c:39 flush_to_ldisc+0x1b0/0x750 drivers/tty/tty_buffer.c:445 process_scheduled_works+0x2b0/0x10d0 kernel/workqueue.c:3229 worker_thread+0x3dc/0x950 kernel/workqueue.c:3391 kthread+0x2a3/0x370 kernel/kthread.c:389 ret_from_fork+0x2d/0x70 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:257 Freed by task 3367: kfree+0x126/0x420 mm/slub.c:4580 gsm_cleanup_mux+0x36c/0x7b0 drivers/tty/n_gsm.c:3160 [n_gsm] gsmld_ioctl+0x395/0x1450 drivers/tty/n_gsm.c:3408 [n_gsm] tty_ioctl+0x643/0x1100 drivers/tty/tty_io.c:2818 [Analysis] gsm_msg on the tx_ctrl_list or tx_data_list of gsm_mux can be freed by multi threads through ioctl,which leads to the occurrence of uaf. Protect it by gsm tx lock.

Quoted source text, attributed separately from HOL analysis.