CVE-2023-27321

highpriority · track · 0EPSS 0.010 · 64 %ileDEEUNLRUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
1.05% (64th) EPSS
CVSS 7.5 · high
Is it mine?
10 products
Check your exposure
Who says so?
8 sources
cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-26

OPC Foundation UA .NET Standard ConditionRefresh Resource Exhaustion Denial-of-Service Vulnerability. This vulnerability allows remote attackers to create a denial-of-service condition on affected installations of OPC Foundation UA .NET Standard. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of OPC UA ConditionRefresh requests. By sending a large number of requests, an attacker can consume all available resources on the server. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-20505.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

02

cvss

Technical severity, 0–10. One row per scoring source.

7.5
010

base score 0–10 · higher = more severe · hover a vector to decode

v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · ENISA EU
v3.07.5highCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · zdi-disclosures@trendmicro.comexploitability 3.9 · impact 3.6
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · CISA US
v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · OSV
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · Siemens ProductCERT DE
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-1325USCWE-1325USCWE-400USCWE-400USCWE-400USCWE-400US
05

affected products (10)

Products and version ranges known to be affected.

06

advisories (5)

Vendor and ecosystem advisories describing this.

  • NCSC-2024-0246Kwetsbaarheden verholpen in Siemens productenNL2024-06-11csaf · ncsc_nlNL

    Siemens heeft kwetsbaarheden verholpen in diverse producten, zoals SCALANCE, SICAM, Tecnomatix, SITOP en PowerSys.

  • NCSC-2024-0282Kwetsbaarheden verholpen in Siemens ProductenNL2024-07-09csaf · ncsc_nlNL

    Siemens heeft kwetsbaarheden verholpen in diverse producten als Mendix, RUGGEDOM, SIMATIC, SINEMA, SIPROTEC en de Engineering Platforms voor diverse systemen.

  • SSA-337522SSA-337522: Multiple Vulnerabilities in TIM 1531 IRC before V2.4.82024-06-11csaf · siemens_psirtDE

    Siemens has released new versions for the affected products and recommends to update to the latest versions.

  • GHSA-vpf7-r2fv-75m9Uncontrolled Resource Consumption in OPC UA .NET Standard Reference Server2023-05-05ghsa · osvUS

    This security update resolves a vulnerability in the OPC UA .NET Standard Reference Server that allows remote attackers to send malicious requests that consume all memory available to the server. https://files.opcfoundation.org/SecurityBulletins/OPC%20Foundation%20Security%20Bulletin%20CVE-2023-27321.pdf

  • ICSA-24-165-06Siemens TIM 1531 IRC2024-06-11icsa · cisa_csaf_otUS

    Siemens has released new versions for the affected products and recommends to update to the latest versions.

07

also known as (6)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisa_csaf_otnvdosvsiemens_psirtncsc_nlNVDCVE.orgMITRE
published 2024-05-07modified 2026-06-17
09

references (7)

External citations — patches, advisories, analysis.

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