CVE-2025-65496: 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…

PriorityP418medium4.3CVSS 3.1

AVNACLPRNUIRSUCNINAL

EPSS

0.23%

13.9th percentile

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
debian	libcoap2	< libcoap3 4.3.5-2 (forky)	libcoap3 4.3.5-2 (forky)
debian	libcoap3	< libcoap3 4.3.5-2 (forky)	libcoap3 4.3.5-2 (forky)
libcoap	libcoap	—	—

CVSS provenance

nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L

osv4.3MEDIUM

vendor_debian4.3MEDIUM

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