No exploitation reportedFix available

CVE-2021-27023

Q: Is CVE-2021-27023 actively exploited?

Active exploitation of CVE-2021-27023 has not been confirmed. Its EPSS score was 1.4% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-2021-27023?

CVE-2021-27023 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

No exploitation reported by the sources we read.

Published2021-11-18
Fixed in7.12.1 · 6.25.1

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A flaw was discovered in Puppet Agent and Puppet Server that may result in a leak of HTTP credentials when following HTTP redirects to a different host. This is similar to CVE-2018-1000007

Timeline

dates in UTC

2021-11-1815:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-27023?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-27023?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD · OSV

Puppet puppet agent

Branch	Affected	Fixed in	Source
7.x	≥ 7.0.0, < 7.12.1	7.12.1	NVD · OSV
6.25	< 6.25.1	6.25.1	NVD · OSV

Puppet puppet enterprise

Branch	Affected	Fixed in	Source
2021.x	≥ 2021.0.0, < 2021.4	2021.4	NVD
2019.8	< 2019.8.9	2019.8.9	NVD

Puppet puppet server

Branch	Affected	Fixed in	Source
7.x	≥ 7.0.0, < 7.4.2	7.4.2	NVD
6.17	< 6.17.1	6.17.1	NVD

1 more product in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Puppet puppet agent to 7.12.1 · 6.25.1

Advisories and patches

puppet.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

NVDCVSS 3.19.8read 2026-10-23
NVDCVSS 2.05read 2026-10-23
FIRST EPSSEPSS score1.4 %2026-10-23
OSVaffected packages—

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2021-11-18
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-27023?

A flaw was discovered in Puppet Agent and Puppet Server that may result in a leak of HTTP credentials when following HTTP redirects to a different host. This is similar to CVE-2018-1000007

Is CVE-2021-27023 actively exploited?

Active exploitation of CVE-2021-27023 has not been confirmed. Its EPSS score was 1.4% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-27023?

CVE-2021-27023 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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