CVE-2026-18785
Received Received - Intake

Use After Free in open62541

Publication date: 2026-08-04

Last updated on: 2026-08-04

Assigner: VulDB

Description
A vulnerability was determined in o6 open62541 ca356b088ada7dee824d1b4acd07c1ff07ce242b. Impacted is the function UA_Client_getRemoteDataTypes of the file examples/custom_datatype/client_types_custom.c. Executing a manipulation can lead to use after free. It is possible to launch the attack on the local host. The exploit has been publicly disclosed and may be utilized. The project closed the issue report, stating that this is not the official way to report a security vulnerability.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-04
Last Modified
2026-08-04
Generated
2026-08-04
AI Q&A
2026-08-04
EPSS Evaluated
N/A
NVD
CVE-2026-18785
EUVD
EUVD-2026-52792

Affected Vendors & Products

Showing 2 associated CPEs
Vendor Product Version / Range
open62541 open62541 *
open62541 open62541 to master (exc)

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-119 The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.
CWE-416 The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

CVE-2026-18785 is a stack overflow vulnerability in the open62541 OPC UA client library. It occurs in the UA_Client_getRemoteDataTypes function due to unbounded recursive traversal of remote DataType references. A malicious OPC UA server can exploit this by returning an ever-growing sequence of new NodeIds, forcing infinite recursion and crashing the client process.

Detection Guidance

Detecting CVE-2026-18785 requires monitoring for stack overflow crashes in the open62541 OPC UA client library. Check logs for segmentation faults or stack overflow errors in applications using the vulnerable function UA_Client_getRemoteDataTypes. Use AddressSanitizer or similar tools to detect stack overflows during OPC UA client operations.

Impact Analysis

This vulnerability can crash the open62541 client application by exhausting the stack through infinite recursion. It may lead to denial of service if the client is part of a critical system. The attack requires a malicious or compromised OPC UA server to trigger the issue during normal protocol interactions.

Compliance Impact

The vulnerability involves a stack overflow in the open62541 OPC UA client library, which could lead to process crashes. This may impact compliance with standards like GDPR or HIPAA by causing disruptions in data processing or availability, potentially violating requirements for data integrity and system reliability.

Mitigation Strategies

Immediately update the open62541 library to a patched version that replaces recursive traversal with an iterative approach and enforces limits on recursion depth and node counts. If updating is not possible, disable custom datatype discovery in OPC UA clients or restrict client-server interactions to trusted servers only.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-18785. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart