OPC Foundation UA .NET Standard 1.04.358.30 toctou

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability has been found in OPC Foundation UA .NET Standard 1.04.358.30 and classified as problematic. Affected by this vulnerability is an unknown function. The manipulation with an unknown input leads to a toctou vulnerability. The CWE definition for the vulnerability is CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. As an impact it is known to affect availability. The summary by CVE is:

This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of OPC Foundation UA .NET Standard 1.04.358.30. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of sessions. The issue results from the lack of proper locking when performing operations on an object. An attacker can leverage this vulnerability to create a denial-of-service condition against the application. Was ZDI-CAN-10295.

The weakness was presented 04/22/2020. This vulnerability is known as CVE-2020-8867 since 02/11/2020. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Neither technical details nor an exploit are publicly available.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.




CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍


VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.3
NVD Vector: 🔍

CNA Base Score: 5.3
CNA Vector (Zero Day Initiative): 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Toctou
CWE: CWE-367 / CWE-362

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍


02/11/2020 🔍
04/22/2020 +71 days 🔍
04/23/2020 +1 days 🔍
06/02/2024 +1501 days 🔍


Advisory: zerodayinitiative.com
Status: Not defined

CVE: CVE-2020-8867 (🔍)


Created: 04/23/2020 11:52 AM
Updated: 06/02/2024 08:59 AM
Changes: 04/23/2020 11:52 AM (33), 04/23/2020 11:57 AM (11), 10/12/2020 06:51 AM (1), 06/02/2024 08:56 AM (16), 06/02/2024 08:59 AM (17)
Complete: 🔍
Cache ID: 44:CCC:40


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