Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.
AV AC PR UI S C I A CVSS EPSS %ile KEV P L N N U N N H 4.6 .0022 12.7 —
AFFECTED Product Versions Fixed zephyr 4.1.0 – —
TIMELINE Jun 2 Reserved by zephyr Jun 24 EXPLOIT PUBLISHED — CVE-2026-10642 (zephyrproject zephyr). Public exploit reference added. Jun 24 Published (CNA: zephyr)
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.
| Date | Event | Detail |
|---|---|---|
| June 2, 2026 | Reserved | Reserved by zephyr |
| June 24, 2026 | EXPLOIT PUBLISHED | EXPLOIT PUBLISHED — CVE-2026-10642 (zephyrproject zephyr). Public exploit reference added. |
| June 24, 2026 | Published | Published (CNA: zephyr) |
| Vendor | Product / Package | Ecosystem | Version introduced | Fixed |
|---|---|---|---|---|
| zephyrproject | zephyr | — | 4.1.0 | — |
Authoritative record: CVE-2026-10642 at cve.org
Vendors: zephyrproject
Weaknesses: CWE-835
This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-10642 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.