Vulnerability Report

CVE-2026-46433

Title: lldpd Heap Buffer Over-read

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-46433.

CWE Category CWE-125
Published Date Jun 09, 2026
Modified Date Jul 23, 2026
Exploit Status Not Found
Score 6.5 CVSS v3.1
Exploit Probability (EPSS)
0.22%

Vulnerability Summary

CVE-2026-46433: 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.

Impacted Vendors

L
lldpd_project 1

Reference Links

https://github.com/lldpd/lldpd/commit/ca931be63a9cae0fcd8e9b6ae4e916d49f141cd6 https://github.com/lldpd/lldpd/pull/787 https://github.com/lldpd/lldpd/releases/tag/1.0.22 https://github.com/lldpd/lldpd/security/advisories/GHSA-2g8p-2h3j-63m3
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
6.5
Attack Vector
ADJACENT_NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-46433 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector ADJACENT_NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected Stack

No specific products linked.