CVE-2016-2166

MEDIUMNVD 6.56.5—
EchelonGraph scoreMEDIUM confidence

This medium-severity CVE scores 6.5 under NVD CVSS v3. EPSS exploit probability: 4.3%, top 10% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
6.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 4%CVSS: 6.5Exploit: NoneExposed: 0

A fix is available — apply it.

The (1) proton.reactor.Connector, (2) proton.reactor.Container, and (3) proton.utils.BlockingConnection classes in Apache Qpid Proton before 0.12.1 improperly use an unencrypted connection for an amqps URI scheme when SSL support is unavailable, which might allow man-in-the-middle attackers to obtain sensitive information or modify data via unspecified vectors.

CVSS v3
6.5
EG Score
6.5(medium)
EG Risk
—
EPSS
90.0%
KEV
Not listed

Published

April 12, 2016

Last Modified

May 6, 2026

References (14)

Vendor Advisories for CVE-2016-2166(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
redhatyaml-cpp-0:0.5.1-7.el7sat2018-02-21redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.apache.qpid:proton-j0.10 ... 0.9.1 (11 versions)0.12.1—

Data Freshness Timeline

(refreshed 12× in last 7d / 42× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-22 22:01 UTCEG score recompute
  2. 2026-07-22 14:04 UTCEPSS rescore
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  64. 2026-05-22 20:54 UTCEG score recompute
  65. 2026-05-22 20:54 UTCVendor advisory
  66. 2026-05-22 08:09 UTCOSV refresh
  67. 2026-05-21 22:40 UTCEPSS rescore
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Frequently asked(5)

What is CVE-2016-2166?
CVE-2016-2166 is a medium vulnerability published on April 12, 2016. The (1) proton.reactor.Connector, (2) proton.reactor.Container, and (3) proton.utils.BlockingConnection classes in Apache Qpid Proton before 0.12.1 improperly use an unencrypted connection for an amqps URI scheme when SSL support is unavailable, which might allow man-in-the-middle attackers to…
When was CVE-2016-2166 disclosed?
CVE-2016-2166 was first published in the National Vulnerability Database on April 12, 2016, with the most recent update on May 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2016-2166 actively exploited?
CVE-2016-2166 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 90.0% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2016-2166?
CVE-2016-2166 has a CVSS v3 base score of 6.5 (NVD).
How do I remediate CVE-2016-2166?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-2166, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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