CVE-2025-65495

Integer signedness error in tls_verify_call_back() in src/coap_openssl.c in OISM libcoap 4.3.5 allows remote attackers to cause a denial of service via a crafted TLS certificate that causes i2d_X509() to return -1 and be misused as a malloc() size parameter.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTNIST
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
mitreCNA
---
---
CISA-ADPADP
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 25%
VendorProductVersion
libcoaplibcoap
4.3.5
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
libcoap2
bullseye
vulnerable
trixie
no-dsa
bookworm
no-dsa
libcoap3
bookworm
no-dsa
trixie
no-dsa
bullseye
postponed
forky
vulnerable
sid
vulnerable
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
libcoap2
questing
dne
plucky
dne
noble
dne
jammy
needs-triage
focal
needs-triage
libcoap3
questing
needs-triage
plucky
needs-triage
noble
needs-triage
jammy
needs-triage
Common Weakness Enumeration
References
https://github.com/obgm/libcoap/issues/1744
https://github.com/obgm/libcoap/pull/1750