CVE-2026-63626

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.

CVSS v3 8.8 HIGH

8.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.9

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/cesanta/mongoose/commit/751f14742dea934bec08a507ab1fecc3673d4903
https://github.com/cesanta/mongoose/releases/tag/7.23
https://github.com/cesanta/mongoose/security/advisories/GHSA-pc66-j6r6-49x9

Configurations

No configuration.

History

14 Oct 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-14 19:17

Updated : 2026-10-16 20:04

NVD link : CVE-2026-63626

Mitre link : CVE-2026-63626

CVE.ORG link : CVE-2026-63626

JSON object : View

Products Affected

No product.

CWE

CWE-122

Heap-based Buffer Overflow

CWE-125

Out-of-bounds Read

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