CVE-2023-3825Network attack vector

Unauthenticated server crash via recursive OPC UA variants

Published Jul 31, 2023 · Updated Oct 21, 2024

Uncontrolled resource consumption in PTC KEPServerEX 6.0 through 6.14.263 allows remote attackers to crash the server via OPC UA. The OPC UA decoder does not detect recursively defined nested Variant objects, so decoding continues until stack exhaustion terminates the process. No authentication or user interaction is required, and the consequence is service interruption rather than data access or modification.

CVSS severity7.5
High
EPSS probability0.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in PTC KEPServerEX 6.0 through 6.14.263 allows remote attackers to crash the server via OPC UA. The OPC UA decoder does not detect recursively defined nested Variant objects, so decoding continues until stack exhaustion terminates the process. No authentication or user interaction is required, and the consequence is service interruption rather than data access or modification.

The record

CVE
CVE-2023-3825
Published
Jul 31, 2023
Updated
Oct 21, 2024
Vendor
PTC Inc.
Product
KEPServerEX
Classifications
CWE-400, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 31, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=6.0 <=6.14.263

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PTC Inc. · KEPServerEXversion=6.0 <=6.14.263

Published CVSS scores

7.5CISACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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