CVE-2023-53805
Vulnerability Scoring
Status: Received on 09 Dec 2025, 01:16 UTC
Published on: 09 Dec 2025, 01:16 UTC
CVSS Release:
CVE-2023-53805: In the Linux kernel, the following vulnerability has been resolved: tty: n_gsm: fix UAF in gsm_cleanup_mux In gsm_cleanup_mux() the 'gsm->dlci' pointer was not cleaned properly, leaving it a dangling pointer after gsm_dlci_release. This leads to use-after-free where 'gsm->dlci[0]' are freed and accessed by the subsequent gsm_cleanup_mux(). Such is the case in the following call trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description+0x63/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x16b/0x1c0 mm/kasan/report.c:451 gsm_cleanup_mux+0x76a/0x850 drivers/tty/n_gsm.c:2397 gsm_config drivers/tty/n_gsm.c:2653 [inline] gsmld_ioctl+0xaae/0x15b0 drivers/tty/n_gsm.c:2986 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb </TASK> Allocated by task 3501: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] gsm_dlci_alloc+0x53/0x3a0 drivers/tty/n_gsm.c:1932 gsm_activate_mux+0x1c/0x330 drivers/tty/n_gsm.c:2438 gsm_config drivers/tty/n_gsm.c:2677 [inline] gsmld_ioctl+0xd46/0x15b0 drivers/tty/n_gsm.c:2986 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 3501: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x80 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0xf1/0x270 mm/slub.c:4559 dlci_put drivers/tty/n_gsm.c:1988 [inline] gsm_dlci_release drivers/tty/n_gsm.c:2021 [inline] gsm_cleanup_mux+0x574/0x850 drivers/tty/n_gsm.c:2415 gsm_config drivers/tty/n_gsm.c:2653 [inline] gsmld_ioctl+0xaae/0x15b0 drivers/tty/n_gsm.c:2986 tty_ioctl+0x8ff/0xc50 drivers/tty/tty_io.c:2816 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb
The exploitability of CVE-2023-53805 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).
No exploitability data is available for CVE-2023-53805.
A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.
Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.
Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.
Above is the CVSS Sub-score Breakdown for CVE-2023-53805, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.
Below is the Impact Analysis for CVE-2023-53805, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.
Unknown
Stay updated with real-time CVE vulnerabilities and take action to secure your systems. Enhance your cybersecurity posture with the latest threat intelligence and mitigation techniques. Develop the skills necessary to defend against CVEs and secure critical infrastructures. Join the top cybersecurity professionals safeguarding today's infrastructures.