CVE-2025-65500

EUVD-2025-198708
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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
4.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
CISA-ADPADP
4.3 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L
Base Score
CVSS 3.x
EPSS Score
Percentile: 33%
Affected Products (NVD)
VendorProductVersion
libcoaplibcoap
4.3.5
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
libcoap2
bookworm
no-dsa
bullseye
vulnerable
libcoap3
bookworm
no-dsa
bullseye
postponed
forky
4.3.5-2
fixed
sid
4.3.5-2
fixed
trixie
4.3.4-1.1+deb13u2
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
libcoap2
focal
needs-triage
jammy
needs-triage
noble
dne
plucky
dne
questing
dne
libcoap3
jammy
needs-triage
noble
needs-triage
plucky
ignored
questing
needs-triage
libcoap
bionic
needs-triage
jammy
dne
noble
dne
plucky
dne
questing
dne
Common Weakness Enumeration
References
https://github.com/obgm/libcoap/issues/1746
https://github.com/obgm/libcoap/pull/1750