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…

PriorityP434high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.22%

12.4th percentile

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.

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

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

osv7.5HIGH

vendor_debian7.5HIGH

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