CVE-2025-65495

7.5 highEPSS 0.3%

High (7.5) in libcoap libcoap. EPSS 0.3% chance of exploitation in the next 30 days.

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.

Severity

CVSS 3.1

7.5 high

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS: 0.3% chance of exploitation in the next 30 days; higher than 17% of CVEs (scores of 2026-10-31)
CWE: CWE-195
Published: 2025-11-24
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

libcoap:libcoap

References

https://github.com/obgm/libcoap/issues/1744
https://github.com/obgm/libcoap/pull/1750

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