NIST deprecates RSA-2048 from 2030. Find every one of them before attackers do.
☕
☕ Maven
Not in CISA KEV
MEDIUM severity

CVE-2016-2166 — proton-j

MEDIUM

CVE-2016-2166 is a medium-severity (CVSS 6.5) Information Exposure vulnerability in org.apache.qpid:proton-j. A fix is available for org.apache.qpid:proton-j — see the affected versions and patch details below.

Moderate severity vulnerability that affects org.apache.qpid:proton-j

Published
Updated
Affected
1 pkg
Patched
1 / 1
Exploits
None indexed
Exploitation data as of Nov 6, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗
4.3%probability of exploitation in next 30 days
Lower Risk0.00%
Lower risk than most CVEs91th percentile — riskier than 91% of all scored CVEsHighest risk
0.00%1.82%3.64%5.47%0.3%4.3%May 26Sep 26Nov 26

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected
☕org.apache.qpid:proton-j

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

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.

Affected Packages

1 total 1 fixed
EcosystemPackageVulnerable rangeFix
☕Mavenorg.apache.qpid:proton-jall versions0.12.1org.apache.qpid:proton-j:0.12.1

Affected Products

2 products · 2 configurations
Application
qpid protonapache
≤ 0.12.0
range
OS
fedorafedoraproject
1 version
23

Detection & mitigation playbook

Open-source dependency

  1. Detect

    Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.qpid:proton-j, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

  2. Fix

    Update org.apache.qpid:proton-j to 0.12.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-2166 is resolved across your whole dependency graph.

  3. Workarounds

    Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

This issue affects the versions of qpid-proton as shipped with Red Hat Satellite version 6. Red Hat Product Security has rated this issue as having Moderate security impact. A future update may address this issue. For additional information, refer to the Issue Severity Classification:…

ProductFixed inAdvisory
Red Hat Satellite 6.3 for RHEL 7createrepo_c-0:0.7.4-1.el7satRHBA-2018:0337

Frequently Asked Questions

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.
O3 Security · Impact-Aware SCA

Is CVE-2016-2166 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works