CVEvulnerability
CVE-2020-12510
7.3 HIGH
Official page ↗
- Status
- Modified
- Published
- 2020-11-19
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.3 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- CVSS 3.1 ([email protected])
- 7.3 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- CVSS 2.0 ([email protected])
- 6.0 MEDIUM — AV:N/AC:M/Au:S/C:P/I:P/A:P
- Weaknesses
- CWE-276
Description
The default installation path of the TwinCAT XAR 3.1 software in all versions is underneath C:\TwinCAT. If the directory does not exist it and further subdirectories are created with permissions which allow every local user to modify the content. The default installation registers TcSysUI.exe for automatic execution upon log in of a user. If a less privileged user has a local account he or she can replace TcSysUI.exe. It will be executed automatically by another user during login. This is also true for users with administrative access. Consequently, a less privileged user can trick a higher privileged user into executing code he or she modified this way. By default Beckhoff’s IPCs are shipped with TwinCAT software installed this way and with just a single local user configured. Thus the vulnerability exists if further less privileged users have been added.
Affected configurations
• beckhoff twincat extended automation runtime 3.1
Related
Weakness · CWE (1)
- CWE-276 Incorrect Default Permissions weakness
References
- https://cert.vde.com/en-us/advisories/vde-2020-037 Third Party Advisory
- https://cert.vde.com/en-us/advisories/vde-2020-037 Third Party Advisory