CVE-2016-2787: The Puppet Communications Protocol in Puppet Enterprise 2015.3.x before 2015.3.3 does not properly validate ce

Routine

MEDIUM 5.3REMOTEDOWNGRADEDOWNGRADE

CVE-2016-2787 is a medium-severity flaw (CVSS 5.3) affecting puppet enterprise, puppet enterprise. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

The Puppet Communications Protocol in Puppet Enterprise 2015.3.x before 2015.3.3 does not properly validate certificates for the broker node, which allows remote non-whitelisted hosts to prevent runs from triggering via unspecified vectors.

Why this priority

Remotely exploitable, no login, no user action

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	5.3 (Medium)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.6% (top 51%)
CISA exploited list	No
Weakness	CWE-284
Published	2017-02-13
Last modified	2026-06-17

Publisher (CNA): MITRE · Vendor: puppet · puppetlabs

Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2017-02-13 18:59 UTCPublished CVE record published
2026-06-17 00:44 UTCUpdated Record last modified

puppet puppet enterprise DOWNGRADE

Affected: 2015.3.2

Fixed in: no fixed release known

Safe to downgrade to: a release before 2015.3.2

1. Check installed version

apt-cache policy puppet-enterprise || rpm -q puppet-enterprise || puppet-enterprise --version

2. No fixed release: DOWNGRADE to a release before 2015.3.2 (Debian / Ubuntu)

apt-cache madison puppet-enterprise sudo apt install puppet-enterprise=<VERSION_BEFORE_2015.3.2> sudo apt-mark hold puppet-enterprise

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list puppet-enterprise sudo dnf downgrade puppet-enterprise-<VERSION_BEFORE_2015.3.2> sudo dnf versionlock add puppet-enterprise

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

puppetlabs puppet enterprise DOWNGRADE

Affected: 2015.3

Fixed in: no fixed release known

Safe to downgrade to: a release before 2015.3

1. Check installed version

apt-cache policy puppet-enterprise || rpm -q puppet-enterprise || puppet-enterprise --version

2. No fixed release: DOWNGRADE to a release before 2015.3 (Debian / Ubuntu)

apt-cache madison puppet-enterprise sudo apt install puppet-enterprise=<VERSION_BEFORE_2015.3> sudo apt-mark hold puppet-enterprise

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list puppet-enterprise sudo dnf downgrade puppet-enterprise-<VERSION_BEFORE_2015.3> sudo dnf versionlock add puppet-enterprise

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2016-2787?

puppet enterprise: downgrade or apply the listed mitigation; puppet enterprise: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2016-2787 being exploited?

CVE-2016-2787 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2016-2787 affect?

CVE-2016-2787 affects puppet enterprise, puppet enterprise. Severity is medium (CVSS 5.3). The Puppet Communications Protocol in Puppet Enterprise 2015.3.x before 2015.3.3 does not properly validate certificates for the broker node, which allows remote non-whitelisted hosts to prevent runs from triggering via unspecified vectors.

How urgent is CVE-2016-2787?

Priority 36/100. Remotely exploitable, no login, no user action

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References

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