CVE-2021-43936

highpriority · attend · 62EPSS 0.358 · 98 %ileexploit · PoCEURUUS

grimoire priorityP1 · Urgent

Exploitable?

Public exploit

2 exploits · PoC

Likely / severe?

35.8% (98th) EPSS

CVSS 10 · high

Is it mine?

5 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cisa_csaf_ot

EPSS · scored 2026-10-27

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.

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

No vendor fix yet; a mitigation is available.

MitigationWebHMIcisa_csaf_ot
Upgrading the platform software to the latest release, Version 4.1
http://webhmi.com.ua/en/2021/09/new-webhmi-firmware-release-4-1/

cvss

Technical severity, 0–10. One row per scoring source.

10.0

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9.8–10

v2.010highAV:N/AC:L/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 10 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.010criticalCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · CISA US

v3.110criticalAV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · ENISA EU

v3.110criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:Hsecondary · ics-cert@hq.dhs.gov USexploitability 3.9 · impact 6

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Hsecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-434USprimaryCWE-434USCWE-434US

exploits (2)

Public proof-of-concept and weaponised exploit code.

EDB-50589WebHMI 4.0 - Remote Code Execution (RCE) (Authenticated)PoC · exploit_db
LongWayHomie/CVE-2021-43936CVE-2021-43936 is a critical vulnerability (CVSS3 10.0) leading to Remote Code Execution (RCE) in WebHMI Firmware.PoC · poc_in_github

affected products (5)

Products and version ranges known to be affected.

WebHMI: All versions prior to 4.1all versionscisa_csaf_otUS
Distributed Data Systems WebHMI< 4.1cisa_csaf_otUS
Distributed Data Systems WebHMI4.1 → 4.1enisa_euvdEU
Distributed Data Systems WebHMI≤ 4.1fstec_bduRU
webhmi webhmi firmware< 4.1nvdUScpe:2.3:o:webhmi:webhmi_firmware:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

ICSA-21-336-03Distributed Data Systems WebHMI2021-12-02icsa · cisa_csaf_otUS
Successful exploitation of these vulnerabilities could allow an administrator account login without password authentication and remote code execution with root privileges.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cisa_csaf_ot nvd NVD CVE.org MITRE

published 2021-12-06modified 2026-06-17

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+5027 more

references (12)

External citations — patches, advisories, analysis.

scry

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