The Puppet Communications Protocol (PCP) Broker incorrectly validates message header sizes. An attacker could use this to crash the PCP Broker, preventing commands from being sent to agents. This is resolved in Puppet Enterprise 2016.4.3 and 2016.5.2.
Conclusion & alert: CVE-2016-9686 is rated Moderate Risk (45.2/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.27%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
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 | 2026-06-15 | 0.38% | 1.27% | +0.90% |
| 2 | 2026-03-03 | 0.52% | 0.38% | -0.14% |
| 3 | 2025-03-30 | — | 0.52% | — |
Full EPSS history (7 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 5.3 | 3.0 | MEDIUM |
|
3.9 | 1.4 | [email protected] |
| 5.0 | 2.0 | MEDIUM |
|
10.0 | 2.9 | [email protected] |
| vendor | priority | summary | link |
|---|---|---|---|
debian
|
unimportant | CVE-2016-9686 unimportant priority: Debian including 1 source packages (puppet), 1 status rows across 1 suites (bullseye): resolved 1. | https://security-tracker.debian.org/tracker/CVE-2016-9686 |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| puppet | puppet_enterprise | >= 2016.4.0, < 2016.4.3 | cpe:2.3:a:puppet:puppet_enterprise:*:*:*:*:*:*:*:* |
| puppet | puppet_enterprise | 2016.5.1 | cpe:2.3:a:puppet:puppet_enterprise:2016.5.1:*:*:*:*:*:*:* |
| URL | Tags |
|---|---|
| https://puppet.com/security/cve/cve-2016-9686 | Vendor Advisory |