Service hang via certificate-validation integer overflow
Published Sep 12, 2023 · Updated Nov 11, 2025
Integer overflow in Siemens OPC UA implementations allows remote attackers to hang affected applications with a crafted certificate. During certificate validation, ANSI C and C++ code mishandles an integer calculation and enters an infinite loop instead of rejecting the malformed certificate. No authentication or user interaction is required; the documented consequence is loss of availability, not data disclosure or modification.
Summary
What happened
Integer overflow in Siemens OPC UA implementations allows remote attackers to hang affected applications with a crafted certificate. During certificate validation, ANSI C and C++ code mishandles an integer calculation and enters an infinite loop instead of rejecting the malformed certificate. No authentication or user interaction is required; the documented consequence is loss of availability, not data disclosure or modification.
The record
- CVE
- CVE-2023-28831
- Published
- Sep 12, 2023
- Updated
- Nov 11, 2025
- Vendor
- Siemens
- Product
- SIMATIC S7-1500 CPU 1518T-4 PN/DP
- Classifications
- CWE-190, T1499, T0814
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 12, 2023CVE publishedPublication date reported by the CVE source.
- Nov 11, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <V3.0.3
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
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
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
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo