CVE-2025-65496
MEDIUMlibcoap 4.3.5 - Denial of Service via Crafted DTLS Handshake
Title source: llmDescription
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.
References (2)
Core 2
Core References
Issue Tracking
https://github.com/obgm/libcoap/issues/1745
Issue Tracking, Patch
https://github.com/obgm/libcoap/pull/1750
Scores
CVSS v3
4.3
EPSS
0.0022
EPSS Percentile
12.0%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-476
Status
published
Products (1)
libcoap/libcoap
4.3.5
Published
Nov 24, 2025
Tracked Since
Feb 18, 2026