Heap-Based Buffer Overflow Vulnerability in o6 open62541 Software
CVE-2026-18784

4.8MEDIUM

Key Information:

Vendor

O6

Status
Open62541
Vendor
CVE Published:
4 August 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2026-18784?

A vulnerability exists in the o6 open62541 software that can lead to a heap-based buffer overflow through the UA_Client_readNodeClassAttribute function within the src/client/ua_client_highlevel.c file. This flaw necessitates local exploitation, allowing attackers to manipulate affected system behavior. While public exploits exist, the project management has indicated that this does not adhere to official vulnerability reporting protocols, which raises concerns over the software's security posture and ongoing risk for users.

Affected Version(s)

open62541 1.5.0

open62541 1.5.1

open62541 1.5.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2026-18784 - Proof of Concept

References

https://vuldb.com/vuln/385786
vdb-entrytechnical-description
https://vuldb.com/vuln/385786/cti
signaturepermissions-required
https://vuldb.com/cve/CVE-2026-18784
third-party-advisory

CVSS V4

Score:
4.8
Severity:
MEDIUM
Confidentiality:
Low
Integrity:
Low
Availability:
Low
Attack Vector:
Local
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Chuan Wei
VULL (VulDB User)
SCU_1CP (VulDB User)
VulDB CNA Team
.