CVE-2023-1256Network attack vector

Unauthenticated data access and alarm tampering

Published Mar 16, 2023 · Updated Jan 16, 2025

Improper authorization in affected AVEVA Plant SCADA and Telemetry Server releases allows remote attackers to read data and alter alarms. AVEVA has not disclosed the affected interface or the authorization check that accepts unauthenticated requests. Network access requires no account or user interaction, and exploitation can expose operational data, falsify alarm states, or interrupt service.

CVSS severity9.8
Critical
EPSS probability0.68%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in affected AVEVA Plant SCADA and Telemetry Server releases allows remote attackers to read data and alter alarms. AVEVA has not disclosed the affected interface or the authorization check that accepts unauthenticated requests. Network access requires no account or user interaction, and exploitation can expose operational data, falsify alarm states, or interrupt service.

The record

CVE
CVE-2023-1256
Published
Mar 16, 2023
Updated
Jan 16, 2025
Vendor
AVEVA
Product
AVEVA Plant SCADA
Classifications
CWE-285, T0866
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 16, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 16, 2025Record 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=2020R2 Update 10
  2. Affected versionversion=2023 Update 10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

AVEVA · AVEVA Plant SCADAversion=2020R2 Update 10; version=2023 Update 10
AVEVA · AVEVA Telemetry Serverversion=2020 R2 SP1

Published CVSS scores

9.8AVEVA Product Security Response CenterCVSS: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.

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

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-285Improper Authorization
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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