{"id":"CVE-2026-13481","summary":"Out-of-bounds read in PTP management TLV TIME parsing in Zephyr net PTP","details":"The IEEE 1588 PTP management-message parser in subsys/net/lib/ptp/tlv.c mishandles the PTP_MGMT_TIME management id. In tlv_mgmt_post_recv(), the PTP_MGMT_TIME case casts mgmt_tlv-\u003edata to a 10-byte struct ptp_timestamp and reads it (then byte-swaps and writes it back) without first checking that the TLV data field is at least sizeof(struct ptp_timestamp). Every sibling management id in the same switch validates its length first; PTP_MGMT_TIME was the only case lacking that check.\n\nThe length passed in is the management data size (tlv-\u003elength - 2), and the upstream guard in ptp_tlv_post_recv() only requires tlv-\u003elength \u003e 2, while msg_tlv_post_recv() validates only that the TLV fits within the received byte count, not a per-id minimum. A peer on the local PTP segment can therefore send a PTP_MSG_MANAGEMENT message carrying a short PTP_MGMT_TIME TLV (data as small as 2 bytes), causing the parser to read and write 8 bytes beyond the validated data. The message type and TLV contents are taken straight off the wire, so the path is reachable by any adjacent attacker when CONFIG_PTP is enabled.\n\nThe over-read and write-back stay within the struct ptp_msg allocation (mgmt_tlv-\u003edata lives in the leading mtu[NET_ETH_MTU] union member, so data + 10 lands at most a few bytes past mtu[], inside the same object), so this is an out-of-bounds read of adjacent in-object memory plus a bounded in-place corruption of the message's parsed timestamp, not past-allocation memory corruption. Impact is limited to minor information exposure of adjacent bytes and corruption of the device's parsed management TIME value; there is no crash on the access and no reachable reference-count corruption.\n\nThe fix adds if (length \u003c sizeof(struct ptp_timestamp)) { return -EBADMSG; } before the cast, matching the other management-id cases and fully closing the receive-path defect.","aliases":["GHSA-mh5r-jxh8-hxwx"],"modified":"2026-09-02T03:45:42.517497061Z","published":"2026-08-26T14:03:49.820Z","database_specific":{"cna_assigner":"zephyr","cwe_ids":["CWE-125"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/13xxx/CVE-2026-13481.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/13xxx/CVE-2026-13481.json"},{"type":"ADVISORY","url":"https://github.com/zephyrproject-rtos/zephyr/security/advisories/GHSA-mh5r-jxh8-hxwx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-13481"},{"type":"FIX","url":"https://github.com/zephyrproject-rtos/zephyr/commit/de98c3721a0e21ca269313997736f4f6193909ef"},{"type":"PACKAGE","url":"https://github.com/zephyrproject-rtos/zephyr"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/zephyrproject-rtos/zephyr","events":[{"introduced":"36940db938a8f4a1e919496793ed439850a221c2"},{"fixed":"dccb09599635bdff17633fa7e9dab014b91dce90"}],"database_specific":{"extracted_events":[{"introduced":"3.7.0"},{"fixed":"4.4.2"}],"source":"AFFECTED_FIELD"}}],"versions":["v4.4.2-rc1","v4.4.1","v4.4.1-rc1","v4.4.0","v4.4.0-rc3","v4.4.0-rc2","v4.4.0-rc1","v4.3.0","v4.3.0-rc3","v4.3.0-rc2","v4.3.0-rc1","v4.2.0","v4.2.0-rc3","v4.2.0-rc2","v4.2.0-rc1","v4.1.0","v4.1.0-rc3","v4.1.0-rc2","v4.1.0-rc1","v4.0.0","v4.0.0-rc3","v4.0.0-rc2","v4.0.0-rc1","v3.7.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-13481.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"}]}