CVE-2021-38432Network attack vector

Unauthenticated code execution via unchecked stack copy

Published Oct 15, 2021 · Updated Sep 16, 2024

Stack-based buffer overflow in FATEK Automation Communication Server 1.13 and earlier allows remote attackers to execute code over the network. The Facon Server on default TCP port 500 copies attacker-controlled data into a stack buffer without validating its length. No authentication or user interaction is required, and successful exploitation runs code in the FaconSvr process context.

CVSS severity9.8
Critical
EPSS probability1.87%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in FATEK Automation Communication Server 1.13 and earlier allows remote attackers to execute code over the network. The Facon Server on default TCP port 500 copies attacker-controlled data into a stack buffer without validating its length. No authentication or user interaction is required, and successful exploitation runs code in the FaconSvr process context.

The record

CVE
CVE-2021-38432
Published
Oct 15, 2021
Updated
Sep 16, 2024
Vendor
FATEK Automation Corporation
Product
FATEK Communication Server
Classifications
CWE-121, T0866
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 15, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=All <=1.13

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

FATEK Automation Corporation · FATEK Communication Serverversion=All <=1.13

Published CVSS scores

9.8ICS-CERTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow
T0866Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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