CVE-2021-27017 | Deserialization of untrusted data

Utilization of a module presented a security risk by allowing the deserialization of untrusted/user supplied data. This is resolved in the Puppet Agent 7.4.0 release.

Published: 2025-02-07 Last update: 2026-04-15 Assigner: [email protected] Source: [email protected]
NVD Status：Deferred，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-27017 is rated Low Risk (35.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.09%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-27017

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-03-18 0.18% 0.09% -0.09%
2 2025-11-21 0.25% 0.18% -0.07%
3 2025-11-18 — 0.25% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-27017

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.6 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:H)
They need powerful rights—admin, root, or similar—before this pays off.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 0.7 5.9 [email protected]

Weakness enumeration for CVE-2021-27017

OS Trackers for CVE-2021-27017

vendor priority summary link
debian unimportant CVE-2021-27017 unimportant priority: Debian including 1 source packages (puppet), 1 status rows across 1 suites (bullseye): resolved 1. https://security-tracker.debian.org/tracker/CVE-2021-27017
redhat medium — https://access.redhat.com/security/cve/CVE-2021-27017
suse medium CVE-2021-27017 severity moderate: SUSE including 2 source package names (puppet, puppet-server), 4 product×package rows across 3 product lines (SUSE Linux Enterprise Module for Advanced Systems Management 12, SUSE Linux Enterprise Point of Service 11 SP3, SUSE Linux Enterprise Server 11 SP4 LTSS): Known Not Affected 4. https://www.suse.com/security/cve/CVE-2021-27017/
ubuntu medium CVE-2021-27017 medium priority: Ubuntu including 1 source packages (puppet), 6 status rows across 6 suites (bionic, focal, groovy, trusty, upstream, xenial): not-affected 6. https://ubuntu.com/security/CVE-2021-27017

Affected software / configurations for CVE-2021-27017

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2021-27017

cvelogic Threat Intelligence