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-2021-36765

24
FAUCET Score

CVE-2021-36765 describes a null pointer dereference vulnerability in CODESYS EtherNet/IP versions prior to 4.1.0.0. This flaw allows an unauthenticated attacker to trigger a denial of service by sending specially crafted EtherNet/IP requests to the affected CODESYS Control runtime system. With a CVSS score of 7.5 (HIGH), it is easily exploitable over the network with low attack complexity, potentially leading to a complete loss of availability. There is currently no public exploit code available, nor is it known to be actively exploited, with minimal community discussion and no media coverage.

Impacted Technologies

VendorProductVersion(s)CPE
< 4.1.0.0CPE matchmatch criteria
cpe:2.3:a:codesys:ethernetip:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

7.5HIGH

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
NONE
Availability Impact
NONE
Exploitability Score
3.9
Impact Score
3.6
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.99%
Probability of exploitation in next 30 days
EPSS Percentile
58.8%
Percentile rank of EPSS score among Peer Group
As of 2026-07-25
Model: v2026.06.15
This CVE's current EPSS score of 0.0099 is in the 34th percentile among its peer group of 51,485 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

customers.codesys.com / index.php
Vendor Advisory