CVE-2025-50518

Description

A use-after-free vulnerability exists in the coap_delete_pdu_lkd function within coap_pdu.c of the libcoap library. This issue occurs due to improper handling of memory after the freeing of a PDU object, leading to potential memory corruption or the possibility of executing arbitrary code. NOTE: this is disputed by the Supplier because it only occurs when an application uses libcoap incorrectly.

CVSS v3.1 Score

9.8

CRITICAL

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

Weakness Type (CWE)

CWE-416 Use After Free

References

Other References

https://github.com/IreneTheITCrowd/blog/blob/main/libcoap-vulnerability.md https://github.com/IreneTheITCrowd/blog/issues/1 https://github.com/obgm/libcoap/issues/1724#issuecomment-3199631257 https://github.com/obgm/libcoap/issues/1724#issuecomment-3234613482

Frequently Asked Questions

What is CVE-2025-50518? +

A use-after-free vulnerability exists in the coap_delete_pdu_lkd function within coap_pdu.c of the libcoap library. This issue occurs due to improper handling of memory after the freeing of a PDU object, leading to potential memory corruption or the possibility of executing arbitrary code. NOTE: this is disputed by the Supplier because it only occurs when an application uses libcoap incorrectly. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2025-50518? +

CVE-2025-50518 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2025-50518? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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