ICSA-21-040-06: ICSA-21-040-06_Siemens JT2Go and Teamcenter Visualization (Update A)

CISA's summary

Summary: Siemens has released version V13.1.0.2 for JT2Go and Teamcenter Visualization to fix multiple vulnerabilities that could be triggered when the products read files in ASM and PAR file formats. If a user is tricked to opening of a malicious file with the affected products, this could lead to application crash, or potentially arbitrary code execution or data extraction on the target host system. Siemens recommends to update to the latest versions and to limit opening of untrusted files from unknown sources in the affected products.

Products, as the advisory lists them

DeSpy has not checked any unit, hardware revision or firmware.

Vulnerabilities in this advisory

• CVE-2020-26991 — CVE-2020-26991 · CWE-822

  Affected applications lack proper validation of user-supplied data when parsing ASM files. This could lead to pointer dereferences of a value obtained from untrusted source. An attacker could leverage this vulnerability to execute code in the context of the current process. (ZDI-CAN-11899)

• CVE-2020-26998 — CVE-2020-26998 · CWE-125

  Affected applications lack proper validation of user-supplied data when parsing of PAR files. This could result in a memory access past the end of an allocated buffer. An attacker could leverage this vulnerability to leak information. (ZDI-CAN-12040)

• CVE-2020-26999 — CVE-2020-26999 · CWE-125

  Affected applications lack proper validation of user-supplied data when parsing of PAR files. This could result in a memory access past the end of an allocated buffer. An attacker could leverage this vulnerability to leak information. (ZDI-CAN-12042)

• CVE-2020-27001 — CVE-2020-27001 · CWE-121

  Affected applications lack proper validation of user-supplied data when parsing of PAR files. This could result in a stack based buffer overflow. An attacker could leverage this vulnerability to execute code in the context of the current process. (ZDI-CAN-12041)

• CVE-2020-27002 — CVE-2020-27002 · CWE-125

  Affected applications lack proper validation of user-supplied data when parsing of PAR files. This could result in a memory access past the end of an allocated buffer. An attacker could leverage this vulnerability to access data in the context of the current process. (ZDI-CAN-12043)

Acknowledgments, as the advisory lists them

• Siemens ProductCERT: reporting these vulnerabilities to CISA.
• Trend Micro Zero Day Initiative: coordinated disclosure
• Carsten Eiram, Risk Based Security: coordinated disclosure of CVE-2020-26991
• Cybersecurity and Infrastructure Security Agency (CISA): coordination efforts

The advisory's legal notice

Siemens Security Advisories are subject to the terms and conditions contained in Siemens' underlying license terms or other applicable agreements previously agreed to with Siemens (hereinafter "License Terms"). To the extent applicable to information, software or documentation made available in or through a Siemens Security Advisory, the Terms of Use of Siemens' Global Website (https://www.siemens.com/terms_of_use, hereinafter "Terms of Use"), in particular Sections 8-10 of the Terms of Use, shall apply additionally. In case of conflicts, the License Terms shall prevail over the Terms of Use.

Sources

• The advisory at cisa.gov
• The CSAF document (JSON)

DeSpy's copy of this version is dated 2026-09-28.