Skip to main content
Public proof of conceptFix available

CVE-2021-43936

A public proof of concept exists; no exploitation attested.

  • Published2021-12-06
  • Fixed in4.1
  • WeaknessCWE-434

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

The software allows the attacker to upload or transfer files of dangerous types to the WebHMI portal, that may be automatically processed within the product's environment or lead to arbitrary code execution.

Timeline

dates in UTC
  1. 2021-12-0618:15CVE publishedNVD
  2. 2021-12-13Exploit-DB entryExploit-DB

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 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-2021-43936?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-43936?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Webhmi webhmi firmwareversion to verify
BranchAffectedFixed in
4.1< 4.14.1

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

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Vendor advisories

  • ICSA-21-336-03 CISA1 known affected

    Distributed Data Systems WebHMI

    WebHMI: All versions prior to 4.1

Full record on NVD

Fix

  1. Update Webhmi webhmi firmware to 4.1
  2. Mitigation from the vendor CISA ICSA-21-336-03 · 1 productUpgrading the platform software to the latest release, Version 4.1

Advisories and patches

Detection

read 2026-11-03 22:42 UTC
Nuclei template
none so far
ProjectDiscovery
Exploit-DB
EDB-50589
Exploit-DB
Proof-of-concept repositories
1 repository, unverifiedLongWayHomie/CVE-2021-43936
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

  • CNACVSS 3.110known since 2026-10-23
  • NVDCVSS 3.19.8read 2026-10-23
  • NVDCVSS 2.010read 2026-10-23
  • NVDweakness (CWE)CWE-434read 2026-10-23
  • FIRST EPSSEPSS score35.8 %read 2026-11-03
  • PoC-in-GitHubproof of concept1read 2026-11-03
  • Exploit-DBdetectionread 2026-11-03

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published
2021-12-06
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2021-43936?

The software allows the attacker to upload or transfer files of dangerous types to the WebHMI portal, that may be automatically processed within the product's environment or lead to arbitrary code execution.

Is CVE-2021-43936 actively exploited?

Active exploitation of CVE-2021-43936 has not been confirmed. Its EPSS score was 35.8% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-43936?

CVE-2021-43936 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Hear about the next vulnerability in your software

Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».

Get alerts for this productCISA KEV additions, November 2026Search CVEs

No credit card required · No monthly cap on website lookups · 250 API requests/month

Go further

Related vulnerabilities

Same product first, then the same vendor advisory and the same publication week.

Back to CVE Database

Sources for this record