CVE-2025-50518

Name	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.
Source	CVE (at NVD; CERT, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libcoap3 (PTS)	bookworm	4.3.1-1	fixed
	trixie	4.3.4-1.1+deb13u1	fixed
	forky, sid	4.3.5-1	fixed

The information below is based on the following data on fixed versions.

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libcoap3	source	(unstable)	(not affected)

Notes

- libcoap3 <not-affected> (Vulnerable code introduced later)
https://github.com/IreneTheITCrowd/blog/blob/main/libcoap-vulnerability.md
https://github.com/obgm/libcoap/issues/1724
Introduced after: https://github.com/obgm/libcoap/commit/ba09d0f6432bf1aabbfe05896a37de2cd718831d