lldpd is an implementation of IEEE 802.1ab (LLDP). Prior to version 1.0.22, lldpddecode() in src/daemon/lldpd.c strips 802.1Q VLAN tags from received Ethernet frames by calling memmove() to shift the frame payload 4 bytes left. The third argument (byte count) is s - 2 ETHERADDRLEN but should be s - 2 ETHERADDRLEN - 4, causing a 4-byte heap buffer over-read past the malloc(hmtu) allocation when the received frame size equals the interface MTU. This issue has been patched in version 1.0.22.

An issue was discovered in lldpd before 1.0.17. By crafting a CDP PDU packet with specific CDPTLVADDRESSES TLVs, a malicious actor can remotely force the lldpd daemon to perform an out-of-bounds read on heap memory. This occurs in cdpdecode in daemon/protocols/cdp.c.

An out-of-bounds read vulnerability exists due to a boundary error when reading SONMP packets. A remote user can send specially crafted packets to the application, trigger a heap-based buffer overflow read and leak memory values from lldpd application or crash it.

Reference:

https://www.cybersecurity-help.cz/vdb/SB2021111808 https://github.com/lldpd/lldpd/commit/73d42680fce8598324364dbb31b9bc3b8320adf7 https://lldpd.github.io/security.html

A flaw was found in multiple versions of Open vSwitch. Specially crafted LLDP packets can cause memory to be lost when allocating data to handle specific optional TLVs, potentially causing a denial of service. The highest threat from this vulnerability is to system availability.

lldpd before 0.8.0 allows remote attackers to cause a denial of service (assertion failure and daemon crash) via a malformed packet.

A buffer overflow was found in the lldpdecode function in daemon/protocols/lldp.c in lldpd. This flaw allows remote attackers to cause a denial of service (daemon crash) and possibly execute arbitrary code via vectors involving large management addresses and TLV boundaries. This threatens the system's confidentiality, integrity, and availability.