{"id":"CVE-2026-102714","details":"`_nx_icmpv6_validate_options()` scans the option area with `while (length \u003e 2)` (`common/src/nx_icmpv6_validate_options.c:79`). An area whose size leaves a one- or two-byte residue exits the loop with that tail unexamined; the residue is not negative, so the function returns `NX_SUCCESS`. Its zero-length rejection never sees those bytes.\n\n\n\nEvery consumer then re-walks the same area, reading a two-byte option header at the residue and subtracting `nx_icmpv6_option_length \u003c\u003c 3` with no zero check and no remaining-length check. Three outcomes follow, selected by bytes the attacker controls.\n\n\n\n**Zero length byte.** The walker subtracts zero and advances zero. All four handlers loop forever — `_nx_icmpv6_process_ra` (`nx_icmpv6_process_ra.c:245, :528`), `_nx_icmpv6_process_ns` (`:251, :329`), `_nx_icmpv6_process_na` (`:147, :156`) and `_nx_icmpv6_process_redirect` (`:247, :350`). The walk runs in the IP thread, which is the highest-priority thread and does not yield inside the loop, so the system stops until a watchdog reset and the frame can be replayed after each one.\n\n\n\n**Non-zero length byte on a short residue.** The three unsigned counters underflow — `2 - 8` becomes `0xFFFFFFFA` — and the walk continues past the packet buffer, reading until it faults or meets a zero length byte and freezes. The Router Advertisement counter is signed and exits cleanly in this case.\n\n\n\n**One-byte residue.** The walker reads a two-byte option header, over-reading one byte.\n\n\n\nDuring a runaway walk, stray bytes parsing as a link-layer address option are copied into the neighbor cache (`nx_icmpv6_process_ns.c:280, :293`) and subsequently used as the destination MAC for frames to that neighbour, placing off-packet memory on the link. Confirmed by inspection, not reproduced.","aliases":["GHSA-39p4-p83c-58hr"],"modified":"2026-10-01T03:31:07.896709760Z","published":"2026-09-29T17:41:28.517Z","database_specific":{"cna_assigner":"eclipse","cwe_ids":["CWE-125","CWE-1287","CWE-191","CWE-835"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102714.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102714.json"},{"type":"ADVISORY","url":"https://github.com/eclipse-threadx/netxduo/security/advisories/GHSA-39p4-p83c-58hr"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-102714"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse-threadx/netxduo","events":[{"introduced":"0"},{"last_affected":"1a0e9e43a03e37ddecfb6b49e9b078d6e1803d05"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"0"},{"last_affected":"6.5.1.202602"}]}}],"versions":["v6.4.1_rel","v6.5.1.202602_rel","v6.5.0.202601_rel","v6.4.5.202504_rel","v6.4.4.202503a","v.6.4.4.202503_rel","v6.4.3_rel","v6.4.2_rel","v6.4.0_rel","v6.3.0_rel","v6.2.1_rel","v6.2.0_rel","v6.1.12_rel","v6.1.11_rel","v6.1.10_rel","v6.1.9_rel","v6.1.8_rel","v6.1.7_rel","v6.1.6_rel","v6.1.5_rel","v6.1.4_rel","v6.1.3_rel","v6.1.2_rel","v6.1_rel","v6.0.2_rel","v6.0.1_rel","v6.0_rel"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-102714.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N"}]}