CVE-2026-46433: Lldpd Project Lldpd

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

lldpd is an implementation of IEEE 802.1ab (LLDP). Prior to version 1.0.22, lldpd_decode() 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 * ETHER_ADDR_LEN but should be s - 2 * ETHER_ADDR_LEN - 4, causing a 4-byte heap buffer over-read past the malloc(h_mtu) allocation when the received frame size equals the interface MTU. This issue has been patched in version 1.0.22.

Affected products

• Lldpd Project Lldpd: before 1.0.22 (fixed in 1.0.22)

Published 2026-06-09. Last modified 2026-07-23.