{"id":"CVE-2023-31129","summary":"Contiki-NG missing NULL pointer check in IPv6 neighbor discovery","details":"The Contiki-NG operating system versions 4.8 and prior can be triggered to dereference a NULL pointer in the message handling code for IPv6 router solicitiations. Contiki-NG contains an implementation of IPv6 Neighbor Discovery (ND) in the module `os/net/ipv6/uip-nd6.c`. The ND protocol includes a message type called Router Solicitation (RS), which is used to locate routers and update their address information via the SLLAO (Source Link-Layer Address Option). If the indicated source address changes, a given neighbor entry is set to the STALE state.\n\nThe message handler does not check for RS messages with an SLLAO that indicates a link-layer address change that a neighbor entry can actually be created for the indicated address. The resulting pointer is used without a check, leading to the dereference of a NULL pointer of type `uip_ds6_nbr_t`.\n\nThe problem has been patched in the `develop` branch of Contiki-NG, and will be included in the upcoming 4.9 release. As a workaround, users can apply Contiki-NG pull request #2271 to patch the problem directly.","aliases":["GHSA-x29r-5qjg-75mq"],"modified":"2026-08-12T03:51:26.009135259Z","published":"2023-05-08T20:51:14.657Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/31xxx/CVE-2023-31129.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-476"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/31xxx/CVE-2023-31129.json"},{"type":"ADVISORY","url":"https://github.com/contiki-ng/contiki-ng/security/advisories/GHSA-x29r-5qjg-75mq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-31129"},{"type":"FIX","url":"https://github.com/contiki-ng/contiki-ng/pull/2271"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/contiki-ng/contiki-ng","events":[{"introduced":"0"},{"last_affected":"9771e9aaebbfbb5633ce69eb9876e0fc70bbcd6f"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"last_affected":"4.8"}],"source":"AFFECTED_FIELD"}}],"versions":["release/v4.8","release/v4.7","release/v4.6","release/v4.5","release/v4.4","release/v4.3","release/v4.2","release/v4.1","release/v4.0","develop/v4.0","fork","develop/v3.x-fork","old/v2.6","2.6-rc0","2.6","2.5-release","old/v2.4","2.4","old/v2.3","2.3","old/v2.2.3","2.2.3","old/v2.2.2","2.2.2","old/v2.2.1","2.2.1","old/v2.2","2.2","old/v2.1","2.1","old/v2.0","2.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-31129.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N"}]}