CVE-2022-25761Network attack vector

Service interruption via unlimited OPC UA chunks

Published Aug 23, 2022 · Updated Sep 16, 2024

Resource exhaustion in o6 Automation GmbH open62541 before 1.2.5 and 1.3-rc1 through 1.3.0 allows remote attackers to interrupt service. UA_ConnectionConfig_default leaves message-size and chunk-count limits at zero, so unfinished OPC UA messages can retain unlimited received chunks. No authentication or user interaction is required; sustained oversized chunks exhaust memory and interrupt the server process without affecting confidentiality or integrity.

CVSS severity7.5
High
EPSS probability1.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in o6 Automation GmbH open62541 before 1.2.5 and 1.3-rc1 through 1.3.0 allows remote attackers to interrupt service. UA_ConnectionConfig_default leaves message-size and chunk-count limits at zero, so unfinished OPC UA messages can retain unlimited received chunks. No authentication or user interaction is required; sustained oversized chunks exhaust memory and interrupt the server process without affecting confidentiality or integrity.

The record

CVE
CVE-2022-25761
Published
Aug 23, 2022
Updated
Sep 16, 2024
Vendor
o6 Automation GmbH
Product
open62541
Classifications
CWE-770, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 23, 2022CVE 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=1.3-rc1 <unspecified
  2. Affected versionversion=unspecified <1.2.5
  3. Affected versionversion=unspecified <1.3.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

o6 Automation GmbH · open62541version=1.3-rc1 <unspecified; version=unspecified <1.2.5; version=unspecified <1.3.1

Published CVSS scores

7.1Snyk CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P
7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/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-770Allocation of Resources Without Limits or Throttling
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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Your stack

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