CVE-2021-27475

Arbitrary code execution via unrestricted object deserialization

Published Mar 23, 2022 · Updated Apr 16, 2025

Object deserialization in Rockwell Automation Connected Components Workbench 12.00.00 and earlier allows attackers to execute arbitrary code. The project-file deserializer accepts a crafted serialized object without restricting which object types it can instantiate. Execution occurs only after a local user opens the malicious project file, and the resulting code runs with that user's application privileges.

CVSS severity8.6
High
EPSS probability2.99%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Object deserialization in Rockwell Automation Connected Components Workbench 12.00.00 and earlier allows attackers to execute arbitrary code. The project-file deserializer accepts a crafted serialized object without restricting which object types it can instantiate. Execution occurs only after a local user opens the malicious project file, and the resulting code runs with that user's application privileges.

The record

CVE
CVE-2021-27475
Published
Mar 23, 2022
Updated
Apr 16, 2025
Vendor
Rockwell Automation
Product
Connected Components Workbench
Classifications
CWE-502, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 23, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 16, 2025Record 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=unspecified <=v12.00.00

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Rockwell Automation · Connected Components Workbenchversion=unspecified <=v12.00.00

Published CVSS scores

8.6Rockwell AutomationCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data
T1204.002Malicious File

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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