ICSA-21-350-13: Siemens Questa and ModelSim
CISA advisory · released 2021-12-16
Source record Collected from CISA's CSAF advisory feed
- Distribution label in the document: TLP:WHITE
- Revision 1, 2021-12-16 (final)
CISA's summary
Risk evaluation: Successful exploitation of this vulnerability could allow access to unencrypted data.
Products, as the advisory lists them
| Vendor | Product | Version |
|---|---|---|
| Siemens | ModelSim Simulation | vers:all/* |
| Siemens | Questa Simulation | vers:all/* |
DeSpy has not checked any unit, hardware revision or firmware.
Vulnerabilities in this advisory
- CVE-2021-42023 · CWE-522
The affected product is vulnerable to insufficiently protected keys required for decrypting intellectual property data, which could allow an attacker to discover the keys and bypass the protection intended by IEEE 1735 standard. CVE-2021-42023 has been assigned to this vulnerability. A CVSS v3 base score of 9.0 has been assigned; the CVSS vector string is (AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N).
Acknowledgments, as the advisory lists them
- Julian Speith, Christof Paar, Max Planck Institute for Security and Privacy: coordinating this vulnerability with Siemens
- Florian Schweins, Alexander May, Ruhr University: coordinating this vulnerability with Siemens
The advisory's legal notice
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Sources
DeSpy's copy of this version is dated 2026-09-28.
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