{"id":"CVE-2026-7426","state":"PUBLISHED","title":"Out-of-Bounds Write via Unsanitized Prefix Length in Router Advertisement Processing in FreeRTOS-Plus-TCP","description":"Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. Users processing IPv4 RA only are not impacted.\n\n\n\nTo mitigate this issue, users should upgrade to the fixed version when available.","publishedAt":"2026-04-29T18:53:52.187Z","updatedAt":"2026-04-29T22:14:34.199Z","severity":{"score":6.1,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N","source":"AMZN"},"assigner":"AMZN","products":["AWS FreeRTOS-Plus-TCP"],"affected":[{"vendor":"AWS","product":"FreeRTOS-Plus-TCP","defaultStatus":"unaffected","versions":[{"version":"4.0.0","status":"affected","lessThan":"4.2.6","versionType":"semver"},{"version":"4.3.0","status":"affected","lessThan":"4.4.1","versionType":"semver"},{"version":"4.2.6","status":"unaffected"},{"version":"4.4.1","status":"unaffected"}],"collectionURL":"https://github.com/FreeRTOS/FreeRTOS-Plus-TCP"}],"references":["https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.4.1","https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/releases/tag/V4.2.6","https://aws.amazon.com/security/security-bulletins/2026-023-aws/","https://github.com/FreeRTOS/FreeRTOS-Plus-TCP/security/advisories/GHSA-97qg-4359-xm3x"],"weaknesses":["CWE-787"],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/7xxx/CVE-2026-7426.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-7426","state":"PUBLISHED","datePublished":"2026-04-29T18:53:52.187Z","dateUpdated":"2026-04-29T22:14:34.199Z","assignerShortName":"AMZN","assignerOrgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","dateReserved":"2026-04-29T14:27:53.201Z"},"containers":{"cna":{"title":"Out-of-Bounds Write via Unsanitized Prefix Length in Router Advertisement Processing in FreeRTOS-Plus-TCP","descriptions":[{"lang":"en","value":"Insufficient validation of the prefix length field in IPv6 Router Advertisement processing in FreeRTOS-Plus-TCP before V4.2.6 and V4.4.1 allows an adjacent network actor to cause memory corruption by sending a crafted Router Advertisement with a prefix length value exceeding the maximum valid length, resulting in a heap buffer overflow. 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