NULL pointer dereference in Codesys Ethernetip

CVE-2021-36765

In CODESYS EtherNetIP before 4.1.0.0, specific EtherNet/IP requests may cause a null pointer dereference in the downloaded vulnerable EtherNet/IP stack that is executed by the CODESYS Control runtime system.

Published · last modified .

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:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.010 (61.0th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 61st percentile — 61.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-36765: held from 0.010 to 0.010.

EPSS over last 30 days · oldest: 0.010 · newest: 0.010 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-36765?
CVE-2021-36765 is a high-severity vulnerability in Codesys Ethernetip, classified under NULL Pointer Dereference. CVSS score: 7.5/10. Published 2021-08-04.
How severe is CVE-2021-36765?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2021-36765 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.