CVE-2026-46433

MEDIUM

lldpd: Heap OOB Read in VLAN Decapsulation memmove

Title source: cna
STIX 2.1

Description

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.

References (4)

Core 4

Scores

CVSS v3 6.5
EPSS 0.0022
EPSS Percentile 13.0%
Attack Vector ADJACENT_NETWORK
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-125
Status published
Products (2)
lldpd/lldpd < 1.0.22
lldpd_project/lldpd < 1.0.22
Published Jun 09, 2026
Tracked Since Jun 10, 2026