{"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":"3.7.0","versionType":"semver"},{"lessThan":"4.4.2","status":"affected","version":"4.4.0","versionType":"semver"}]}],"cveId":"CVE-2026-12632","cwes":["CWE-125"],"description":"Zephyr's Precision Time Protocol receive handler ptp_msg_post_recv() in subsys/net/lib/ptp/msg.c takes the 4-bit message type straight off the wire via ptp_msg_type() (msg->header.type_major_sdo_id & 0xF, range 0-15) and uses it to index the msg_size[] table. That table only defines entries up to PTP_MSG_MANAGEMENT (0xD), giving it ARRAY_SIZE == 14. Before the fix there was no upper-bound check, so the undefined types 0xE and 0xF indexed one or two int slots past the end of the array — an out-of-bounds read of adjacent read-only data.\n\nThe out-of-bounds value is then reused as a length: it gates msg_size[type] > cnt, and when it is small or negative it makes cnt - msg_size[type] a large positive budget passed to msg_tlv_post_recv(), whose TLV loop then walks the message suffix past the received bytes, performing further out-of-bounds reads and in-place byte-swap writes on memory beyond the message slab.\n\nThe defect is reached directly from the network: ptp_port_event_gen() in subsys/net/lib/ptp/port.c reads a PTP frame with ptp_transport_recv() and calls ptp_msg_post_recv() with the attacker-chosen type. PTP uses UDP multicast or raw Ethernet (0x88F7) and is unauthenticated, so any host on the same link can trigger the indexing on a CONFIG_PTP-enabled node with no preconditions.\n\nThe reliably reproducible impact is a denial of service (fault/crash); a limited memory-corruption path exists but depends on the build-specific value adjacent to msg_size[], which the attacker cannot tune. The fix rejects type >= ARRAY_SIZE(msg_size) with -EBADMSG before any indexing.","epss":{"date":"2026-11-03","percentile":0.21073,"score":0.00285},"exploits":[],"kev":null,"metrics":[{"score":6.5,"severity":"medium","source":"CNA: zephyr","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"},{"score":6.5,"severity":"medium","source":"NVD: vulnerabilities@zephyrproject.org","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}],"modifiedAt":1793769520560,"publishedAt":1787086543955,"references":[{"source":"CNA: zephyr","tags":["patch"],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/30dabd4c2f2e3641732c00111cd80b5c524c0136"},{"source":"CNA: zephyr","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-frjr-h396-7wh4"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/commit/30dabd4c2f2e3641732c00111cd80b5c524c0136"},{"source":"vulnerabilities@zephyrproject.org","tags":[],"url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-frjr-h396-7wh4"}],"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/30dabd4c2f2e3641732c00111cd80b5c524c0136"}],"revision":"8c43bde6c284e0ec77c5416dc5c02028cc95f2d1aa3cd8d2c86196e0f5904b82","sources":[{"modifiedAt":1793768376437,"name":"CNA: zephyr","retrievedAt":1793769026992,"url":"https://www.cve.org/CVERecord?id=CVE-2026-12632"},{"modifiedAt":1793769520560,"name":"NVD","retrievedAt":1793772956706,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12632"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1793769048732,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-12632"}],"ssvc":{"assessedAt":1787145696731,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"Out-of-bounds read in Zephyr PTP message parsing from unvalidated message type","updatedAt":1793772956706}