CVE-2021-27017Network attack vector

Managed-node compromise via undisclosed deserialization

Published Feb 7, 2025 · Updated Feb 7, 2025

Deserialization of untrusted data in Puppet Agent before 7.4.0 allows remote authenticated users with high privileges to compromise managed nodes. Puppet has not published the affected module or deserialization routine, nor the operation performed on attacker-controlled data. The record requires a network path and high privileges, but does not identify the exact data access, modification, or service interruption achieved.

CVSS severity6.6
Medium
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Deserialization of untrusted data in Puppet Agent before 7.4.0 allows remote authenticated users with high privileges to compromise managed nodes. Puppet has not published the affected module or deserialization routine, nor the operation performed on attacker-controlled data. The record requires a network path and high privileges, but does not identify the exact data access, modification, or service interruption achieved.

The record

CVE
CVE-2021-27017
Published
Feb 7, 2025
Updated
Feb 7, 2025
Vendor
Puppet
Product
Puppet Agent
Classifications
CWE-502
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 7, 2025CVE publishedPublication date reported by the CVE source.
  2. Feb 7, 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=0.0.0 <7.4.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Puppet · Puppet Agentversion=0.0.0 <7.4.0

Published CVSS scores

6.6PerforceCVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/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)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-502Deserialization of Untrusted Data

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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