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.
To mitigate this issue, users should upgrade to the fixed version when available.
"}],"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. Users processing IPv4 RA only are not impacted.\n\n\n\nTo mitigate this issue, users should upgrade to the fixed version when available."}],"impacts":[{"capecId":"CAPEC-153","descriptions":[{"lang":"en","value":"CAPEC-153: Input Data 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1.0.1"}}},"cveMetadata":{"assignerOrgId":"ff89ba41-3aa1-4d27-914a-91399e9639e5","assignerShortName":"AMZN","cveId":"CVE-2026-7426","datePublished":"2026-04-29T18:53:52.187Z","dateReserved":"2026-04-29T14:27:53.201Z","dateUpdated":"2026-04-29T22:14:34.199Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-04-29 20:16:32","lastModifiedDate":"2026-04-29 23:16:20","problem_types":["CWE-787","CWE-787 CWE-787: Out-of-bounds 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Write via Unsanitized Prefix Length in Router Adve","CVE":"CVE-2026-7426","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"7426","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"Out-of-Bounds Write via Unsanitized Prefix Length in Router Adve"}]}}}