CVE-2026-5589: zephyrproject-rtos zephyr Out-of-bounds Write

Vulnerability summary

CVE-2026-5589 is a medium (CVSS 6.3) Out-of-bounds Write vulnerability in zephyrproject-rtos zephyr. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.8% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 04-06-2026
   PublishedVulnerability first disclosed.
2. 15-10-2026
   Last modifiedVulnerability information updated.

Description

An integer underflow in bt_mesh_sol_recv() in the Bluetooth Mesh solicitation handling (subsys/bluetooth/mesh/solicitation.c) leads to an out-of-bounds write. When CONFIG_BT_MESH_OD_PRIV_PROXY_SRV is enabled, the function parses solicitation PDUs from raw BLE advertising payloads. The AD parsing loop reads an attacker-controlled length byte (reported_len) and computes reported_len - 3 without checking that reported_len >= 3. When reported_len is less than 3, the subtraction is performed in signed int arithmetic and yields a negative value that bypasses the length guard and is then implicitly converted to a very large size_t when passed to net_buf_simple_pull_mem(). In builds without assertions, this wraps the buffer length and advances the data pointer far out of bounds, so subsequent reads dereference invalid memory. A nearby BLE device can trigger this with a non-connectable advertisement carrying a UUID16 AD structure and a crafted length byte, with no pairing or prior association required, potentially leading to denial of service or arbitrary code execution.

• CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.