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.
History

Fri, 23 Oct 2026 00:45:00 +0000

Type Values Removed Values Added
First Time appeared Cesanta
Cesanta mongoose
Vendors & Products Cesanta
Cesanta mongoose

Sat, 17 Oct 2026 00:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 14 Oct 2026 18:45:00 +0000

Type Values Removed Values Added
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.
Title Mongoose: ppp_handle_ipv6cp() uses attacker-controlled length without bounds check — OOB read and heap overflow (PPP/PPPoE, MG_ENABLE_IPV6)
Weaknesses CWE-122
CWE-125
References
Metrics cvssV3_1

{'score': 8.8, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2026-10-14T18:26:16.830Z

Updated: 2026-10-15T15:06:33.386Z

Reserved: 2026-07-17T14:11:15.481Z

Link: CVE-2026-63626

cve-icon Vulnrichment

Updated: 2026-10-15T13:53:23.803Z

cve-icon NVD

Status : Deferred

Published: 2026-10-14T19:17:18.570

Modified: 2026-10-16T20:04:29.760

Link: CVE-2026-63626

cve-icon Redhat

No data.