{"cve":"CVE-2026-53922","nvd":{"published":"2026-10-12T22:17:04.623","modified":"2026-10-16T20:04:29.760","status":"Deferred","description":"odhcpd is the DHCPv6, DHCPv4, and router-advertisement server used by OpenWrt. In commit cfddd56 and earlier, an unauthenticated host on the same link can first obtain two bindings through normal DHCPv6 SOLICIT and REQUEST exchanges and then send a crafted RENEW containing multiple IA_NA options. An earlier matched IA consumes most of the response buffer, an unmatched IA causes the build_ia() status branch to write and return a NOBINDING response larger than the remaining space, and a subsequent matched IA is processed after dhcpv6_ia_handle_IAs() subtracts that over-return from an unsigned size_t. The resulting underflow disables subsequent length checks and permits attacker-controlled IA_ADDR serialization beyond the 512-byte stack buffer pdbuf in handle_client_request(). The stack canary terminates odhcpd, and sustained packets can repeatedly disrupt DHCPv6 service while procd respawns the process. The observed configuration does not establish code execution.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":6.5},"cwes":["CWE-121","CWE-191"],"references":["https://github.com/openwrt/odhcpd/commit/c6792bac3905d4bf726d914e9994f6d4b98c5b57","https://github.com/openwrt/odhcpd/commit/d08dbcc527cb8f296cd132c1e5bca696e77095b8","https://github.com/openwrt/odhcpd/commit/d168c27fb6a55a07ac4c888e09ff2f41e263d7b7","https://github.com/openwrt/odhcpd/commit/d329a15413387027453644cd363dca06ade28328","https://github.com/openwrt/odhcpd/security/advisories/GHSA-7hcw-g2jh-pqv5"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:58:52.678897993+00:00"},"epss":{"cve":"CVE-2026-53922","score":0.00613,"percentile":0.49074,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}