The Zephyr PL011 UART driver (drivers/serial/uart_pl011.c) contains an unbounded software loop in pl011_irq_tx_enable() that repeatedly invokes the interrupt-driven application callback while the TX interrupt mask bit (PL011_IMSC_TXIM) is set, to work around the controller's level-transition TX-interrupt behavior. When CTS hardware flow control is enabled (devicetree hw-flow-control or runtime UART_CFG_FLOW_CTRL_RTS_CTS) and the wired serial peer de-asserts CTS, the controller stops draining the TX FIFO; pl011_fifo_fill() then returns 0 on every call while the application still has pending data and therefore never disables the TX interrupt. The loop condition never clears, so the thread that called uart_irq_tx_enable() (e.g. h4_send() in the Bluetooth HCI H4 driver) spins indefinitely, hanging the executing context and stalling the transport — a denial of service (CWE-835). An attacker controlling the device attached to the UART's CTS line can trigger the hang by withholding CTS during transmission. Because that peer is the device wired to the UART — which may be a removable or external module (e.g. an off-board Bluetooth controller on the HCI H4 link) rather than a permanently-bonded on-PCB part — the attack vector is scored Adjacent (AV:A) rather than Physical; the security subcommittee should confirm the vector against the specific deployment. Impact is availability only; there is no memory-safety, confidentiality, or integrity consequence. The vulnerable loop was introduced in commit b783bc8448ef (Feb 2025) and shipped in releases v4.1.0 through v4.4.0. The fix breaks out of the loop when CTS is blocking and arms the CTS modem-status interrupt to resume transmission when CTS re-asserts.
Remote Denial of Service in LwM2M do_write_op_tlv. Zephyr versions >= 1.14.2, >= 2.2.0 contain Improper Input Validation (CWE-20), Loop with Unreachable Exit Condition ('Infinite Loop') (CWE-835). For more information, see https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-g9mg-fj58-6fqh
A denial-of-service issue in the dns implemenation could cause an infinite loop.
Loop with Unreachable Exit Condition ('Infinite Loop') vulnerability in Arm Ltd Bifrost GPU Kernel Driver, Arm Ltd Valhall GPU Kernel Driver, Arm Ltd Arm 5th Gen GPU Architecture Kernel Driver allows a non-privileged user process to make valid GPU memory processing operations, including via WebGL or WebGPU, to cause the whole system to become unresponsive.This issue affects Bifrost GPU Kernel Driver: r44p1, from r46p0 through r49p0, from r50p0 through r51p0; Valhall GPU Kernel Driver: r44p1, from r46p0 through r49p0, from r50p0 through r51p0; Arm 5th Gen GPU Architecture Kernel Driver: r44p1, from r46p0 through r49p0, from r50p0 through r51p0.