{"id":"CVE-2026-63626","aliases":["DEBIAN-CVE-2026-63626","EUVD-2026-101599","GHSA-pc66-j6r6-49x9","UBUNTU-CVE-2026-63626"],"status":"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.","severity":{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00239,"percentile":0.15078,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-122","CWE-125"],"published":"2026-10-14T18:26:16Z","modified":"2026-10-28T20:17:47Z","fixes":[{"ecosystem":"Debian:14","package":"mongoose","fixed_in":["7.23+ds-1"],"sources":["osv"]}],"affected":[{"source":"osv","ecosystem":"Debian:14","package":"mongoose","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.23+ds-1"}]}],"versions":["7.21+ds-1","7.21+ds-1~bpo13+1","7.21+ds-2","7.22+ds-1","7.22+ds-1~bpo13+1","7.23+ds-1~bpo13+1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"mongoose","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["7.21+ds-1","7.21+ds-2","7.22+ds-1","7.23+ds-1"]}],"products":[{"vendor":"automattic","product":"mongoose"},{"vendor":"cesanta","product":"mongoose"}],"references":[{"url":"https://github.com/cesanta/mongoose/security/advisories/GHSA-pc66-j6r6-49x9","tags":["x_refsource_CONFIRM","advisory"]},{"url":"https://github.com/cesanta/mongoose/commit/751f14742dea934bec08a507ab1fecc3673d4903","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/cesanta/mongoose/releases/tag/7.23","tags":["x_refsource_MISC","web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63626.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63626","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-63626","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2026-63626","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-63626","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-63626","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.","status":"published","published":"2026-10-14T18:26:16.83Z","modified":"2026-10-15T15:06:33.386Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"cwes":["CWE-122","CWE-125"],"updated_at":"2026-11-02T14:19:55.914391Z"}],"euvd":[{"id":"EUVD-2026-101599","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.","status":"published","published":"2026-10-14T18:26:16Z","modified":"2026-10-15T15:06:33Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T17:00:14.20041Z"}],"nvd":[{"id":"CVE-2026-63626","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.","status":"published","published":"2026-10-14T19:17:18.57Z","modified":"2026-10-16T20:04:29.76Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"}],"cwes":["CWE-122","CWE-125"],"updated_at":"2026-11-02T14:12:59.328869Z"}],"osv":[{"id":"CVE-2026-63626","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.","status":"published","published":"2026-10-14T18:26:16.83Z","modified":"2026-10-28T11:17:04.556462455Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"cwes":["CWE-122","CWE-125"],"updated_at":"2026-11-02T15:45:13.306117Z"},{"id":"DEBIAN-CVE-2026-63626","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.","status":"published","published":"2026-10-14T19:17:18.57Z","modified":"2026-10-23T17:47:43.650737827Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:57.932517Z"},{"id":"UBUNTU-CVE-2026-63626","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.","status":"published","published":"2026-10-14T19:17:00Z","modified":"2026-10-28T20:17:47.969834186Z","cvss":[{"version":"3.1","score":8.8,"vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-02T16:56:43.630667Z"}]}}