CVE-2025-65495

Published Nov 24, 2025 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:2.3:a:libcoap:libcoap:4.3.5:-:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Libcoap
Libcoap libcoap
Vendors & Products Libcoap
Libcoap libcoap
Type Values Removed Values Added
Weaknesses CWE-195
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description 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.
References
Weaknesses

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Nov 24, 2025, 2:41 PM
Reserved
Nov 18, 2025, 12:00 AM
Status
Analyzed
Published
Nov 24, 2025, 2:15 PM
Modified
Nov 5, 2026, 1:10 PM