CVE-2025-65493

High

Description

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

SeverityHigh

CVSS7.5

Exploit probability—

ProductLibcoap

PublishedNov 24, 2025

First seenNov 24, 2025

Weakness typeCWE-476NULL pointer dereference

How to fix

Patches

github.com/obgm/libcoap/pull/1750

Affected products

Product	Affected versions	Fixed in
libcoap libcoap	4.3.5	—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.