CVE-2020-27263Network attack vector

Crash and data disclosure via crafted OPC UA

Published Jan 13, 2021 · Updated Aug 4, 2024

Heap-based buffer overflow in affected Kepware-derived OPC UA servers allows remote attackers to crash them or read data. The OPC UA interface mishandles a crafted message while opening it and overruns a heap buffer; further code-level details are not public. No authentication or user interaction is required when a reachable OPC UA endpoint is enabled, and effects are limited to server crash and data disclosure.

CVSS severity9.1
Critical
EPSS probability4.94%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap-based buffer overflow in affected Kepware-derived OPC UA servers allows remote attackers to crash them or read data. The OPC UA interface mishandles a crafted message while opening it and overruns a heap buffer; further code-level details are not public. No authentication or user interaction is required when a reachable OPC UA endpoint is enabled, and effects are limited to server crash and data disclosure.

The record

CVE
CVE-2020-27263
Published
Jan 13, 2021
Updated
Aug 4, 2024
Vendor
PTC Inc.
Product
ThingWorx Industrial Connectivity
Classifications
CWE-787, CWE-122, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 13, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=All versions
  2. Affected versionversion=v6.8 and v6.9

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PTC Inc. · ThingWorx Industrial Connectivityversion=All versions; version=v6.8 and v6.9
Software Toolbox · TOP Serverversion=All 6.x versions
Rockwell Automation · KEPServer Enterpriseversion=All versions
PTC Inc. · KEPServerEXversion=v6.0 to v6.9
GE Digital · Industrial Gateway Serverversion=v7.66; version=v7.68.804
PTC Inc. · OPC Aggregatorversion=All versions

Published CVSS scores

9.1Rockwell AutomationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
9.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-122Heap-based Buffer Overflow
T1499Endpoint Denial of Service

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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