CVE-2025-65500

Severity CVSS v4.0:

Pending analysis

Type:

CWE-476 NULL Pointer Dereference

Publication date:

24/11/2025

Last modified:

25/11/2025

Description

NULL pointer dereference in coap_dtls_generate_cookie() in src/coap_openssl.c in OISM libcoap 4.3.5 allows remote attackers to cause a denial of service via a crafted DTLS handshake that triggers SSL_get_SSL_CTX() to return NULL.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L CVSS v3.1 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): Required
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): Low

Base Score 3.x

4.30

Severity 3.x

MEDIUM

References to Advisories, Solutions, and Tools

https://github.com/obgm/libcoap/issues/1746
https://github.com/obgm/libcoap/pull/1750