CVE-2024-40493: Keith-Cullen Freecoap

Critical severity, CVSS 9.8. EPSS: 0.8% chance of exploitation in the next 30 days.

Null Pointer Dereference in `coap_client_exchange_blockwise2` function in Keith Cullen FreeCoAP 1.0 allows remote attackers to cause a denial of service and potentially execute arbitrary code via a specially crafted CoAP packet that causes `coap_msg_get_payload(resp)` to return a null pointer, which is then dereferenced in a call to `memcpy`.

Affected products

• Keith-Cullen Freecoap: version 1.0 only

Published 2024-10-22. Last modified 2026-06-17.