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TI-2024-33518 Aliases CVE-2024-50073GHSA-76p7-w946-wvch

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

Priority LOW 36CWE-416Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 5 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-416 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00261 17th percentileScored 2026-11-07
Fix Partial Linux (Linux): 5.16, 5.19, 5.20 +4Red Hat: 1 advisoryRed Hat: 5 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
LinuxLinux5.15.209 to before 5.16; 5.18.18 to before 5.19; 5.19.2 to before 5.205.16, 5.19, 5.20Patch availableCNA
LinuxLinux6.0 and later6.1.114, 6.6.58, 6.11.5, 6.12Patch availableCNA
  • Linux VendorLinux Affected 5.15.209 to before 5.16; 5.18.18 to before 5.19; 5.19.2 to before 5.20 Fixed in 5.16, 5.19, 5.20 Patch available CNA
  • Linux VendorLinux Affected 6.0 and later Fixed in 6.1.114, 6.6.58, 6.11.5, 6.12 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*before 6.1.114; 6.2 to before 6.6.58; 6.7 to before 6.11.5VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:*6.12 rc1VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:*6.12 rc2VulnerableLinux
cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:*6.12 rc3VulnerableLinux
  • cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions before 6.1.114; 6.2 to before 6.6.58; 6.7 to before 6.11.5 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.12:rc1:*:*:*:*:*:* Versions 6.12 rc1 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.12:rc2:*:*:*:*:*:* Versions 6.12 rc2 Vulnerable ·Linux
  • cpe:2.3:o:linux:linux_kernel:6.12:rc3:*:*:*:*:*:* Versions 6.12 rc3 Vulnerable ·Linux

Remediation

  • Fix · CNA Linux (Linux) Fixed in 5.16, 5.19, 5.20
  • Fix · CNA Linux (Linux) Fixed in 6.1.114, 6.6.58, 6.11.5, 6.12

Red Hat 1 advisory

  • RHSA-2025:6966 Released 2025-05-13 · Red Hat rating Moderate
    kernel security update
    • Red Hat Enterprise Linux AppStream (v. 9) kernel-64k-debug-devel-5.14.0-570.12.1.el9_6, kernel-64k-debug-devel-matched-5.14.0-570.12.1.el9_6, kernel-64k-devel-5.14.0-570.12.1.el9_6 +12
    • Red Hat Enterprise Linux BaseOS (v. 9) kernel-5.14.0-570.12.1.el9_6, kernel-64k-5.14.0-570.12.1.el9_6, kernel-64k-core-5.14.0-570.12.1.el9_6 +28
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) kernel-tools-libs-devel-5.14.0-570.12.1.el9_6, libperf-5.14.0-570.12.1.el9_6
    • Red Hat Enterprise Linux Real Time (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-64k-5.14.0-570.12.1.el9_6, kernel-rt-64k-core-5.14.0-570.12.1.el9_6 +21
    • Red Hat Enterprise Linux Real Time for NFV (v. 9) kernel-rt-5.14.0-570.12.1.el9_6, kernel-rt-core-5.14.0-570.12.1.el9_6, kernel-rt-debug-5.14.0-570.12.1.el9_6 +11

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix planned: Will not fix
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time (v. 9)Fixed RHSA-2025:6966
Red Hat Enterprise Linux Real Time for NFV (v. 9)Fixed RHSA-2025:6966
Not affected: 1 product
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-50073
  2. 2026-10-03 Alias added: GHSA-76p7-w946-wvch
  3. 2026-10-29 Affected versions changed · Red Hat

References

  • TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
  • TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
  • TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
  • TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
  • TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
See all 15278 →

Sources