{"id":"CVE-2026-63626","state":"PUBLISHED","title":"Mongoose: ppp_handle_ipv6cp() uses attacker-controlled length without bounds check — OOB read and heap overflow (PPP/PPPoE, MG_ENABLE_IPV6)","description":"Mongoose is an embedded web server and network library. Prior to 7.23, ppp_handle_ipv6cp() in src/l2_ppp.c trusts the 16-bit IPv6CP len field without checking it against the received payload size. On a PPP or PPPoE link using MG_ENABLE_TCPIP and MG_ENABLE_IPV6, an unauthenticated adjacent peer can complete the required LCP exchange and send a short Configure-Request with an oversized length, causing ppp_tx_frame() to read beyond recv_queue.buf and write beyond tx.buf. The same length misuse can also expose adjacent heap bytes in a reply or hang the event loop through find_opt(). This issue is fixed in version 7.23.","publishedAt":"2026-10-14T18:26:16.830Z","updatedAt":"2026-10-15T15:06:33.386Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["cesanta mongoose"],"affected":[{"vendor":"cesanta","product":"mongoose","versions":[{"version":"< 7.23","status":"affected"}]}],"references":["https://github.com/cesanta/mongoose/security/advisories/GHSA-pc66-j6r6-49x9","https://github.com/cesanta/mongoose/commit/751f14742dea934bec08a507ab1fecc3673d4903","https://github.com/cesanta/mongoose/releases/tag/7.23"],"weaknesses":["CWE-122","CWE-125"],"ingestedAt":"2026-10-29T20:12:41.951Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/63xxx/CVE-2026-63626.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63626","state":"PUBLISHED","datePublished":"2026-10-14T18:26:16.830Z","dateUpdated":"2026-10-15T15:06:33.386Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-07-17T14:11:15.481Z"},"containers":{"cna":{"title":"Mongoose: ppp_handle_ipv6cp() uses attacker-controlled length without bounds check — OOB read and heap overflow (PPP/PPPoE, MG_ENABLE_IPV6)","descriptions":[{"lang":"en","value":"Mongoose is an embedded web server and network library. Prior to 7.23, ppp_handle_ipv6cp() in src/l2_ppp.c trusts the 16-bit IPv6CP len field without checking it against the received payload size. On a PPP or PPPoE link using MG_ENABLE_TCPIP and MG_ENABLE_IPV6, an unauthenticated adjacent peer can complete the required LCP exchange and send a short Configure-Request with an oversized length, causing ppp_tx_frame() to read beyond recv_queue.buf and write beyond tx.buf. The same length misuse can also expose adjacent heap bytes in a reply or hang the event loop through find_opt(). This issue is fixed in version 7.23."}],"affected":[{"vendor":"cesanta","product":"mongoose","versions":[{"version":"< 7.23","status":"affected"}]}],"references":[{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-pc66-j6r6-49x9","name":"https://github.com/cesanta/mongoose/security/advisories/GHSA-pc66-j6r6-49x9","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/cesanta/mongoose/commit/751f14742dea934bec08a507ab1fecc3673d4903","name":"https://github.com/cesanta/mongoose/commit/751f14742dea934bec08a507ab1fecc3673d4903","tags":["x_refsource_MISC"]},{"url":"https://github.com/cesanta/mongoose/releases/tag/7.23","name":"https://github.com/cesanta/mongoose/releases/tag/7.23","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"ADJACENT_NETWORK","availabilityImpact":"HIGH","baseScore":8.8,"baseSeverity":"HIGH","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-122","lang":"en","description":"CWE-122: Heap-based Buffer Overflow","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-125","lang":"en","description":"CWE-125: Out-of-bounds Read","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-14T18:26:16.830Z"},"source":{"advisory":"GHSA-pc66-j6r6-49x9","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-15T13:53:23.078452Z","id":"CVE-2026-63626","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-15T15:06:33.386Z"}}]}}}