What is CVE-2016-4970?

CVE-2016-4970 is a high-severity vulnerability in Apache Cassandra, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 7.5/10. Published 2017-04-13.

How severe is CVE-2016-4970?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2016-4970 known to be exploited?

8 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Vulnerability in Apache Cassandra

CVE-2016-4970

handler/ssl/OpenSslEngine.java in Netty 4.0.x before 4.0.37.Final and 4.1.x before 4.1.1.Final allows remote attackers to cause a denial of service (infinite loop).

Published 2017-04-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.113 (96.0th percentile), scored 2026-11-01.

Moderate probability of exploitation in the next 30 days — watch for active exploitation reports. 96th percentile — 96.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.113 · newest: 0.113 · change: 0.000

Affected products

Apache Cassandra — versions 3.11.4
Netty
Red Hat Jboss Data Grid — versions 7.1
Red Hat Jboss Middleware Text-Only Advisories — versions 1.0

Weakness classification (CWE)

CWE-835 — Loop with Unreachable Exit Condition (Infinite Loop)

Public proof-of-concept exploits

References

rhn.redhat.com/errata/RHSA-2017-0179.html (vendor-advisory, Third Party Advisory)
rhn.redhat.com/errata/RHSA-2017-1097.html (vendor-advisory, Third Party Advisory)
netty.io/news/2016/06/07/4-1-1-Final.html (Release Notes, Vendor Advisory)
www.securityfocus.com/bid/96540 (VDB Entry, Third Party Advisory, vdb-entry)
github.com/netty/netty/pull/5364 (Patch, Third Party Advisory)
wiki.opendaylight.org/view/Security_Advisories (Third Party Advisory)
netty.io/news/2016/06/07/4-0-37-Final.html (Release Notes, Vendor Advisory)
bugzilla.redhat.com/show_bug.cgi (VDB Entry, Third Party Advisory, Issue Tracking)
lists.apache.org/thread.html/afaa5860e3a6d327eb96c3d82cbd2f5996de815a16854ed1ad… (mailing-list)

Frequently asked questions

What is CVE-2016-4970?: CVE-2016-4970 is a high-severity vulnerability in Apache Cassandra, classified under Loop with Unreachable Exit Condition (Infinite Loop). CVSS score: 7.5/10. Published 2017-04-13.
How severe is CVE-2016-4970?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2016-4970 known to be exploited?: 8 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.