CVE-2026-46433

Description

A flaw was found in lldpd, an implementation of IEEE 802.1ab (LLDP). A remote attacker on the adjacent network can send specially crafted Ethernet frames with 802.1Q VLAN (Virtual Local Area Network) tags. This can cause a 4-byte heap buffer over-read, leading to a denial of service (DoS) due to an application crash. This vulnerability occurs when the received frame size equals the interface Maximum Transmission Unit (MTU).

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score6.5N/AN/A
Attack VectorAdjacent NetworkN/AN/A
Attack ComplexityLowN/AN/A
Privileges RequiredNoneN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityNoneN/AN/A
Integrity ImpactNoneN/AN/A
Availability ImpactHighN/AN/A

Vector

Red Hat: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Understanding the Weakness (CWE)

CWE-131

Integrity,Availability,Confidentiality

Technical Impact: DoS: Crash, Exit, or Restart; Execute Unauthorized Code or Commands; Read Memory; Modify Memory

If the incorrect calculation is used in the context of memory allocation, then the software may create a buffer that is smaller or larger than expected. If the allocated buffer is smaller than expected, this could lead to an out-of-bounds read or write (CWE-119), possibly causing a crash, allowing arbitrary code execution, or exposing sensitive data.

Frequently Asked Questions

Not sure what something means? Check out our Security Glossary.

Want to get errata notifications? Sign up here.