Vulnerabilities
- CVSS
- 5.3 Medium
- Vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:L- EPSS
- 0.12%
- Risk score
- 1.2
- Published
- 2026-02-14
- Status
- Published
In the Linux kernel, the following vulnerability has been resolved:
Bluetooth: hci_uart: fix null-ptr-deref in hci_uart_write_work
hci_uart_set_proto() sets HCI_UART_PROTO_INIT before calling
hci_uart_register_dev(), which calls proto->open() to initialize
hu->priv. However, if a TTY write wakeup occurs during this window,
hci_uart_tx_wakeup() may schedule write_work before hu->priv is
initialized, leading to a NULL pointer dereference in
hci_uart_write_work() when proto->dequeue() accesses hu->priv.
The race condition is:
CPU0 CPU1
---- ----
hci_uart_set_proto()
set_bit(HCI_UART_PROTO_INIT)
hci_uart_register_dev()
tty write wakeup
hci_uart_tty_wakeup()
hci_uart_tx_wakeup()
schedule_work(&hu->write_work)
proto->open(hu)
// initializes hu->priv
hci_uart_write_work()
hci_uart_dequeue()
proto->dequeue(hu)
// accesses hu->priv (NULL!)
Fix this by moving set_bit(HCI_UART_PROTO_INIT) after proto->open()
succeeds, ensuring hu->priv is initialized before any work can be
scheduled.
A flaw was found in the Linux kernel's Bluetooth HCI UART driver. A race condition exists where the `hci_uart_write_work()` function may attempt to access uninitialized private data if a TTY write wakeup occurs during the protocol initialization phase. This can lead to a NULL pointer dereference, potentially causing a system crash and resulting in a Denial of Service (DoS).
Coverage 3
vulnerability
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and data integrity compromise. The vulnerabilities…
vulnerability
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and data integrity compromise. These vulnerabiliti…
threat-intel
Multiple vulnerabilities have been discovered in the Linux kernel of Ubuntu. Some of these vulnerabilities allow for privilege escalation, data confidentiality breaches, and denial of service attacks. The vulnerabilities…
Advisories and references