CVE-2021-38434

Code execution via PDW parser out-of-bounds write

Published Oct 18, 2021 · Updated Sep 16, 2024

Unexpected sign extension in FATEK Automation WinProladder 3.30 and earlier allows remote attackers to execute arbitrary code via a crafted PDW file. The PDW parser sign-extends an attacker-controlled value and uses it in a write outside the bounds of an allocated buffer. Exploitation requires a user to open the malicious project file or visit a malicious page, and the resulting code runs in the WinProladder process context.

CVSS severity7.8
High
EPSS probability0.97%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Unexpected sign extension in FATEK Automation WinProladder 3.30 and earlier allows remote attackers to execute arbitrary code via a crafted PDW file. The PDW parser sign-extends an attacker-controlled value and uses it in a write outside the bounds of an allocated buffer. Exploitation requires a user to open the malicious project file or visit a malicious page, and the resulting code runs in the WinProladder process context.

The record

CVE
CVE-2021-38434
Published
Oct 18, 2021
Updated
Sep 16, 2024
Vendor
FATEK Automation Corporation
Product
WinProladder
Classifications
CWE-194, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 18, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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  1. Affected versionversion=All <=3.30

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

FATEK Automation Corporation · WinProladderversion=All <=3.30

Published CVSS scores

7.8NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
7.8ICS-CERTCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-194Unexpected Sign Extension
T1204.002User Execution: Malicious File

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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