Zephyr Project up to 4.4.2 CC1200 Driver ieee802154_cc1200.c verify_rxfifo_validity buffer overflow

Summaryinfo

A vulnerability was found in Zephyr Project Zephyr up to 4.4.2 and classified as critical. This impacts the function verify_rxfifo_validity of the file drivers/ieee802154/ieee802154_cc1200.c of the component CC1200 Driver. Such manipulation leads to buffer overflow. This vulnerability is uniquely identified as CVE-2026-75084. The attack can be launched remotely. No exploit exists. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability was found in Zephyr Project Zephyr up to 4.4.2 and classified as critical. Affected by this issue is the function verify_rxfifo_validity of the file drivers/ieee802154/ieee802154_cc1200.c of the component CC1200 Driver. The manipulation with an unknown input leads to a buffer overflow vulnerability. Using CWE to declare the problem leads to CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. Impacted is integrity, and availability. CVE summarizes:

The CC1200 sub-GHz IEEE 802.15.4 driver takes the PHY packet length from the first byte of the radio's RX FIFO in get_packet_length() and validates it in verify_rxfifo_validity() (drivers/ieee802154/ieee802154_cc1200.c). That validation only enforced a lower bound (pkt_len < 3); its second clause rejects a FIFO that holds more bytes than declared and therefore never bounds large values. Because the driver configures the radio for variable packet length with PKT_LEN = 0xFF, the length byte is an over-the-air value of 0-255 that reached net_pkt_rx_alloc_with_buffer() and the subsequent SPI burst read unclamped. An unauthenticated attacker within radio range can transmit a frame that presents a length byte above the IEEE 802.15.4 maximum of 127 while the chip's 128-byte RX FIFO has not overflowed, so the driver's RX_FIFO_ERROR pre-check does not fire. Reaching this state depends on RF framing and timing, since the RX thread is driven off the PKT_SYNC_RXTX signal and may sample the FIFO before a packet is complete; no pairing, authentication, or user interaction is required. With the default CONFIG_NET_BUF_FIXED_DATA_SIZE and CONFIG_NET_BUF_DATA_SIZE=128, an allocation larger than one fragment is satisfied by a chain of fragments, but read_rxfifo_content() performs a single SPI burst of pkt_len bytes into the first fragment's buf->data and then calls net_buf_add() with the same length. A length above 128 therefore writes up to 127 bytes past the end of a fragment in the contiguous rx_bufs pool and leaves a net_buf whose len exceeds its capacity. The overflowing bytes are FIFO-underflow output rather than attacker-chosen data, so the practical impact is network-buffer-pool corruption and crashes rather than a controlled write. Only builds that enable CONFIG_IEEE802154_CC1200 with an attached CC1200 radio are affected.

The advisory is available at github.com. This vulnerability is handled as CVE-2026-75084 since 08/17/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit.

Applying the patch 26a8b8294bf28523c7aa2f15cf728517980ee593 is able to eliminate this problem.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Project Management Software

Vendor

• Zephyr Project

Name

• Zephyr

Version

• 4.4.0
• 4.4.1
• 4.4.2

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CPE 2.2info

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