IM
IronMonkey Threat Research

CVE-2024-43893 MEDIUM

Published: 2024-08-26 | Last Modified: 2026-05-12 | Status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: serial: core: check uartclk for zero to avoid divide by zero Calling ioctl TIOCSSERIAL with an invalid baud_base can result in uartclk being zero, which will result in a divide by zero error in uart_get_divisor(). The check for uartclk being zero in uart_set_info() needs to be done before other settings are made as subsequent calls to ioctl TIOCSSERIAL for the same port would be impacted if the uartclk check was done where uartclk gets set. Oops: divide error: 0000 PREEMPT SMP KASAN PTI RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580) Call Trace: <TASK> serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576 drivers/tty/serial/8250/8250_port.c:2589) serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502 drivers/tty/serial/8250/8250_port.c:2741) serial8250_set_termios (drivers/tty/serial/8250/8250_port.c:2862) uart_change_line_settings (./include/linux/spinlock.h:376 ./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222) uart_port_startup (drivers/tty/serial/serial_core.c:342) uart_startup (drivers/tty/serial/serial_core.c:368) uart_set_info (drivers/tty/serial/serial_core.c:1034) uart_set_info_user (drivers/tty/serial/serial_core.c:1059) tty_set_serial (drivers/tty/tty_io.c:2637) tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791) __x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907 fs/ioctl.c:893 fs/ioctl.c:893) do_syscall_64 (arch/x86/entry/common.c:52 (discriminator 1) arch/x86/entry/common.c:83 (discriminator 1)) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Rule: add

Additional Descriptions (1)

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: serial: core: verifique uartclk en busca de cero para evitar la división por cero. Llamar a ioctl TIOCSSERIAL con un baud_base no válido puede resultar en que uartclk sea cero, lo que resultará en un error de división por cero en uart_get_divisor (). La verificación de que uartclk sea cero en uart_set_info() debe realizarse antes de realizar otras configuraciones, ya que las llamadas posteriores a ioctl TIOCSSERIAL para el mismo puerto se verían afectadas si la verificación de uartclk se realizó donde se establece uartclk. Vaya: error de división: 0000 PREEMPT SMP KASAN PTI RIP: 0010:uart_get_divisor (drivers/tty/serial/serial_core.c:580) Seguimiento de llamadas: serial8250_get_divisor (drivers/tty/serial/8250/8250_port.c:2576 drivers /tty/serial/8250/8250_port.c:2589) serial8250_do_set_termios (drivers/tty/serial/8250/8250_port.c:502 drivers/tty/serial/8250/8250_port.c:2741) serial8250_set_termios (drivers/tty/serial/ 8250/8250_port.c:2862) uart_change_line_settings (./include/linux/spinlock.h:376 ./include/linux/serial_core.h:608 drivers/tty/serial/serial_core.c:222) uart_port_startup (drivers/tty/ serial/serial_core.c:342) uart_startup (drivers/tty/serial/serial_core.c:368) uart_set_info (drivers/tty/serial/serial_core.c:1034) uart_set_info_user (drivers/tty/serial/serial_core.c:1059) tty_set_serial (drivers/tty/tty_io.c:2637) tty_ioctl (drivers/tty/tty_io.c:2647 drivers/tty/tty_io.c:2791) __x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:907 fs /ioctl.c:893 fs/ioctl.c:893) do_syscall_64 (arch/x86/entry/common.c:52 (discriminador 1) arch/x86/entry/common.c:83 (discriminador 1)) Entry_SYSCALL_64_after_hwframe (arch /x86/entry/entry_64.S:130) Regla: agregar

CVSS Metrics

Base Score: 5.5 (MEDIUM)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactNONE
Integrity ImpactNONE
Availability ImpactHIGH

Source: [email protected]

Type: Primary

Exploitability Score: 1.8

Impact Score: 3.6

Weaknesses

Source Type Description
[email protected] Primary
en CWE-369

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7fd36a6e5e40> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd36b9210c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd3686c9180> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd36936cfc0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd36a6e7c80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd385665680> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd385bdaf80> Operating System
linux linux_kernel 6.11 <built-in method update of dict object at 0x7fd369428240> Operating System
linux linux_kernel 6.11 <built-in method update of dict object at 0x7fd3686cb740> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:6.11:rc1:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:6.11:rc2:*:*:*:*:*:*

References