Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2016-6303

53
FAUCET Score

CVE-2016-6303 is a critical integer overflow vulnerability in the MDC2_Update function of OpenSSL versions prior to 1.1.0, affecting products like Node.js. This flaw allows remote attackers to trigger an out-of-bounds write, leading to a denial of service (application crash) or potentially other unspecified impacts. With a CVSS score of 9.8 (CRITICAL), it presents a high-risk attack vector requiring no user interaction. While there is no known active exploitation or public exploit code (Metasploit, Nuclei, ExploitDB), the vulnerability has garnered significant community discussion and media coverage, indicating its perceived importance.

Impacted Technologies

VendorProductVersion(s)CPE
< 0.12.16CPE matchmatch criteria
cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*
>= 4.0.0, < 4.6.0CPE matchmatch criteria
cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*
>= 6.0.0, < 6.6.0CPE matchmatch criteria
cpe:2.3:a:nodejs:node.js:*:*:*:*:*:*:*:*
1.0.1CPE matchmatch criteria
cpe:2.3:a:openssl:openssl:1.0.1:*:*:*:*:*:*:*
1.0.1aCPE matchmatch criteria
cpe:2.3:a:openssl:openssl:1.0.1a:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

9.8CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
5.9
CvssVersion
3.1

Exploit Intelligence

EPSS Score
31.99%
Probability of exploitation in next 30 days
EPSS Percentile
98.1%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.3199 is in the 95th percentile among its peer group of 36,897 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (2)

oraclepatch availablevia nvd_reference
View patch
redhatpatch availablevia nvd_reference
View patch

Vendor Advisories (1)

redhatCVE-2016-6303Moderate

openssl: Integer overflow in MDC2_Update()

Aug 20, 2016

References

kb.juniper.net / InfoCenter/index
Third Party Advisory
bto.bluecoat.com / security-advisory/sa132
Third Party Advisory
bugzilla.redhat.com / show_bug.cgi
Issue TrackingPatchThird Party Advisory
cert-portal.siemens.com / productcert/pdf/ssa-412672.pdf
git.openssl.org
kb.pulsesecure.net / articles/Pulse_Security_Advisories/SA40312
Third Party Advisory
nodejs.org / en/blog/vulnerability/september-2016-security-releases
Third Party Advisory
security.freebsd.org / advisories/FreeBSD-SA-16:26.openssl.asc
Third Party Advisory
tenable.com / security/tns-2016-16
Third Party Advisory
tenable.com / security/tns-2016-20
Third Party Advisory
tenable.com / security/tns-2016-21
Third Party Advisory
www-01.ibm.com / support/docview.wss
Third Party Advisory
oracle.com / technetwork/security-advisory/cpuapr2018-3678067.html
PatchThird Party Advisory
oracle.com / technetwork/security-advisory/cpujan2018-3236628.html
PatchThird Party Advisory
oracle.com / technetwork/security-advisory/cpujul2017-3236622.html
PatchThird Party Advisory
oracle.com / technetwork/security-advisory/cpuoct2016-2881722.html
PatchThird Party Advisory
oracle.com / technetwork/security-advisory/cpuoct2017-3236626.html
PatchThird Party Advisory
securityfocus.com / bid/92984
Third Party AdvisoryVDB Entry
securitytracker.com / id/1036885
Third Party AdvisoryVDB Entry