Unauthenticated service interruption via crafted TCP packets
Published Dec 13, 2022 · Updated Apr 21, 2025
Improper input validation in Siemens SIMATIC controllers allows remote attackers to interrupt service using crafted TCP/102 packets. The affected ISO-on-TCP packet-processing path mishandles specially crafted packets, but Siemens has not disclosed the faulty parsing operation. No authentication or user interaction is required; successful exploitation interrupts the controller and therefore the industrial process it controls.
Summary
What happened
Improper input validation in Siemens SIMATIC controllers allows remote attackers to interrupt service using crafted TCP/102 packets. The affected ISO-on-TCP packet-processing path mishandles specially crafted packets, but Siemens has not disclosed the faulty parsing operation. No authentication or user interaction is required; successful exploitation interrupts the controller and therefore the industrial process it controls.
The record
- CVE
- CVE-2021-40365
- Published
- Dec 13, 2022
- Updated
- Apr 21, 2025
- Vendor
- Siemens
- Product
- SIMATIC S7-1500 CPU 1518T-4 PN/DP
- Classifications
- CWE-20, T1499, T0814
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 13, 2022CVE publishedPublication date reported by the CVE source.
- Apr 21, 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?
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- Affected versionversion=All versions < V3.0.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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