CVE-2025-65496 Null dereference in n/a
Remote attackers can cause denial of service in libcoap via a crafted DTLS handshake triggering a null pointer dereference.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-65496?
CVE-2025-65496 is a medium-severity vulnerability in n/a, published on 24 Nov 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official 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.
Weakness: CWE-476
Which versions are affected by CVE-2025-65496?
It affects 1 product.
Products include Libcoap Libcoap.
How do I fix CVE-2025-65496?
Upgrade to a fixed version.
Is CVE-2025-65496 being exploited?
There is no known exploitation of CVE-2025-65496 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as DEBIAN-CVE-2025-65496, GHSA-7wxw-9w8h-rrr5, UBUNTU-CVE-2025-65496.