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 update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-4970 is rated High Risk (66.4/100): CVSS High severity, with high exploitation likelihood (EPSS 11.26%, 95th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +3.03% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-4970

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 8.23% 11.26% +3.03%
2 2025-03-30 16.89% 8.23% -8.66%
3 2025-03-29 — 16.89% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-4970

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
7.8 2.0 HIGH
AV:N/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
 10.0 6.9 [email protected]

Weakness enumeration for CVE-2016-4970

GitHub Security Advisory for CVE-2016-4970

GHSA-rv63-gqm8-9w8q · Severity: high · Ecosystem: maven — Loop with Unreachable Exit Condition in Netty

OS Trackers for CVE-2016-4970

vendor priority summary link
debian not yet assigned CVE-2016-4970 not yet assigned priority: Debian including 1 source packages (netty), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2016-4970
redhat medium — https://access.redhat.com/security/cve/CVE-2016-4970
ubuntu medium CVE-2016-4970 medium priority: Ubuntu including 1 source packages (netty), 24 status rows across 24 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, precise, questing, trusty, upstream, wily, xenial, yakkety, zesty): not-affected 22, needed 1, released 1. https://ubuntu.com/security/CVE-2016-4970

NVD evaluator notes for CVE-2016-4970

Comment: CWE-835: Loop with Unreachable Exit Condition ('Infinite Loop')

Affected software / configurations for CVE-2016-4970

Vendor Product Version Raw CPE
netty netty >= 4.0.20, < 4.0.37 cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
netty netty >= 4.1.0, < 4.1.1 cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:*
redhat jboss_data_grid 7.1 cpe:2.3:a:redhat:jboss_data_grid:7.1:*:*:*:*:*:*:*
redhat jboss_middleware_text-only_advisories 1.0 cpe:2.3:a:redhat:jboss_middleware_text-only_advisories:1.0:*:*:*:*:middleware:*:*
apache cassandra 3.11.4 cpe:2.3:a:apache:cassandra:3.11.4:*:*:*:*:*:*:*

References for CVE-2016-4970

cvelogic Threat Intelligence