{"affected":[{"defaultStatus":"unaffected","ecosystem":"https://github.com/zephyrproject-rtos/zephyr","packageName":"zephyr","product":"zephyr","source":"CNA: zephyr","vendor":"zephyrproject","versions":[{"lessThan":"4.3.2","status":"affected","version":"4.3.0","versionType":"semver"},{"lessThan":"4.5.0","status":"affected","version":"4.4.0","versionType":"semver"}]}],"cveId":"CVE-2026-75085","cwes":["CWE-125"],"description":"The STM32WBA IEEE 802.15.4 driver in drivers/ieee802154/ieee802154_stm32wba.c computed the packet length of a received frame as pkt_len = rx_frame->length - IEEE802154_FCS_LENGTH without first checking that the radio-reported length could hold an FCS. pkt_len is a uint8_t, so a reported length of 0 or 1 wrapped to 254 or 255. The only bound on the resulting value was __ASSERT_NO_MSG(pkt_len <= CONFIG_NET_BUF_DATA_SIZE), which compiles to nothing in the default production configuration (CONFIG_ASSERT=n).\n\nThe length originates in the ST link-layer receive-done metadata (p_metadata->length, stored by stm32wba_802154_receive_done()), and ultimately in the PHY header of a frame received over the air, so it is influenced by any attacker within radio range of the device. Reaching the underflow requires the vendor link layer to surface a frame shorter than the FCS with no error; the driver performed no validation of its own on that value.\n\nWhen the underflow occurs, stm32wba_802154_rx_thread() calls net_pkt_write(pkt, rx_frame->psdu, pkt_len) with a length of about 254 bytes against a receive buffer that holds at most one PHY packet (IEEE802154_MAX_PHY_PACKET_SIZE, 127 bytes). This reads roughly 128 bytes past the end of the radio receive buffer and copies that adjacent memory into a network packet that is submitted to the networking stack, giving an out-of-bounds read with a potential disclosure of adjacent RAM plus needless oversized packet allocation in the RX thread.\n\nThe fix rejects a frame whose reported length is smaller than IEEE802154_FCS_LENGTH before the subtraction, and replaces the compiled-out assertion with a runtime length check that drops oversized frames — matching the runtime check already present in drivers/ieee802154/ieee802154_nrf5.c.","epss":{"date":"2026-11-03","percentile":0.10588,"score":0.00205},"exploits":[],"kev":null,"metrics":[{"score":4.2,"severity":"medium","source":"CNA: zephyr","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L","version":"3.1"},{"score":4.2,"severity":"medium","source":"NVD: vulnerabilities@zephyrproject.org","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L","version":"3.1"}],"modifiedAt":1793769540830,"publishedAt":1791996362993,"references":[{"source":"CNA: zephyr","tags":["patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/46f8af4f5ee472abc13b0291c44fdfe4ed879aaa"},{"source":"CNA: zephyr","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-w7pm-4r95-c9vr"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/46f8af4f5ee472abc13b0291c44fdfe4ed879aaa"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-w7pm-4r95-c9vr"}],"remediation":[{"kind":"fix","source":"CNA: zephyr","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/zephyrproject-rtos/zephyr/commit/46f8af4f5ee472abc13b0291c44fdfe4ed879aaa"}],"revision":"b15b3e5c58b2eb5ace87d0a8dda77a1ba410ea2a599da30e24bd61649e539ccc","sources":[{"modifiedAt":1793768468079,"name":"CNA: zephyr","retrievedAt":1793772768369,"url":"https://www.cve.org/CVERecord?id=CVE-2026-75085"},{"modifiedAt":1793769540830,"name":"NVD","retrievedAt":1793772982066,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-75085"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793772771384,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-75085"}],"ssvc":{"assessedAt":1792164226554,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Out-of-bounds read from received-frame length underflow in the STM32WBA IEEE 802.15.4 driver","updatedAt":1793772982066}