CVE-2026-76992Network attack vectorHinoki check available

Service interruption via unbounded gateway-response allocation

Published Sep 30, 2026 · Updated Sep 30, 2026

Uncontrolled memory allocation in the CODESYS Gateway Client allows remote attackers controlling a gateway to exhaust memory and interrupt service. The client trusts a gateway response's size field and allocates memory without an appropriate upper bound. Exploitation requires a malicious gateway to return a crafted response to a connecting client; the resulting exhaustion renders that client unavailable without reported data access or modification.

CVSS severityUnavailable
Unscored
EPSS probability0.33%
Next 30 days · Oct 19, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Uncontrolled memory allocation in the CODESYS Gateway Client allows remote attackers controlling a gateway to exhaust memory and interrupt service. The client trusts a gateway response's size field and allocates memory without an appropriate upper bound. Exploitation requires a malicious gateway to return a crafted response to a connecting client; the resulting exhaustion renders that client unavailable without reported data access or modification.

The record

CVE
CVE-2026-76992
Published
Sep 30, 2026
Updated
Sep 30, 2026
Vendor
CODESYS GmbH
Product
CODESYS OPC DA Server SL
Classifications
T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 30, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 30, 2026Record 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=3.0.0.0 <3.5.22.40

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

CODESYS GmbH · CODESYS OPC DA Server SLversion=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS PLCHandlerversion=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS Gatewayversion=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS Runtime Toolkitversion=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS Development System 3version=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS Edge Gateway for Windowsversion=3.0.0.0 <3.5.22.40
CODESYS GmbH · CODESYS Edge Gateway for Linuxversion=3.15.0.0 <4.23.0.0
CODESYS GmbH · CODESYS HMI SLversion=3.0.0.0 <3.5.22.40

Published CVSS scores

No CVSS assessment is available in this record.

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.

Activity data is delayed. The latest report is Sep 28, 2026.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 22, 2026Sep 28, 2026
Latest reporting daySep 28, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

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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