CVE-2026-46433

Severity CVSS v4.0:

Pending analysis

Type:

CWE-125 Out-of-bounds Read

Publication date:

09/06/2026

Last modified:

11/06/2026

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.

Impact

Vector 3.x

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS v3.1 Severity and Metrics:

Base Score: 6.50 MEDIUM
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Attack Vector (AV): Adjacent
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): None
Integrity (I): None
Availability (A): High