No exploitation reported

CVE-2021-33542

No exploitation reported by the sources we read.

Published2021-06-25
WeaknessCWE-824

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Phoenix Contact Classic Automation Worx Software Suite in Version 1.87 and below is affected by a remote code execution vulnerability. Manipulated PC Worx or Config+ projects could lead to a remote code execution when unallocated memory is freed because of incompletely initialized data. The attacker needs to get access to an original bus configuration file (*.bcp) to be able to manipulate data inside. After manipulation the attacker needs to exchange the original file by the manipulated one on the application programming workstation. Availability, integrity, or confidentiality of an application programming workstation might be compromised by attacks using these vulnerabilities. Automated systems in operation which were programmed with one of the above-mentioned products are not affected.

Timeline

dates in UTC

2021-06-2519:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 18:48 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-33542?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-33542?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Phoenixcontact config\+

Branch	Affected	Fixed in	Source
1.87	≤ 1.87	no fix published	NVD

Phoenixcontact pc worx

Branch	Affected	Fixed in	Source
1.87	≤ 1.87	no fix published	NVD

Phoenixcontact pc worx express

Branch	Affected	Fixed in	Source
1.87	≤ 1.87	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CNACVSS 3.17.8read 2026-10-23
NVDCVSS 3.17read 2026-10-23
NVDCVSS 2.05.1read 2026-10-23
CNAweakness (CWE)CWE-824read 2026-10-23
NVDweakness (CWE)CWE-824read 2026-10-23
FIRST EPSSEPSS score1.8 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
Published: 2021-06-25
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2021-33542?

Is CVE-2021-33542 actively exploited?

Active exploitation of CVE-2021-33542 has not been confirmed. Its EPSS score was 1.8% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-33542?

CVE-2021-33542 has a CVSS v3 base score of 7 (HIGH severity), with vector string CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

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