GCVE-110-CERTCC-2020-114757

### Overview Acronis True Image, Cyber Backup, and Cyber Protection all contain privilege escalation vulnerabilities, which can allow an unprivileged Windows user to be able to run arbitrary code with SYSTEM privileges. ### Description **CVE-2020-10138** Acronis Cyber Backup 12.5 and Cyber Protect 15 include an OpenSSL component that specifies an `OPENSSLDIR` variable as a subdirectory within `C:\jenkins_agent\`. Acronis Cyber Backup and Cyber Protect contain a privileged service that uses this OpenSSL component. Because unprivileged Windows users can create subdirectories off of the system root, a user can create the appropriate path to a specially-crafted `openssl.cnf` file to achieve arbitrary code execution with SYSTEM privileges. **CVE-2020-10139** Acronis True Image 2021 includes an OpenSSL component that specifies an `OPENSSLDIR` variable as a subdirectory within `C:\jenkins_agent\`. Acronis True Image contains a privileged service that uses this OpenSSL component. Because unprivileged Windows users can create subdirectories off of the system root, a user can create the appropriate path to a specially-crafted `openssl.cnf` file to achieve arbitrary code execution with SYSTEM privileges. **CVE-2020-10140** Acronis True Image 2021 fails to properly set ACLs of the `C:\ProgramData\Acronis` directory. Because some privileged processes are executed from the `C:\ProgramData\Acronis` directory, an unprivileged user can achieve arbitrary code execution with SYSTEM privileges by placing a DLL in one of several paths within `C:\ProgramData\Acronis`. ### Impact By placing a specially-crafted `openssl.cnf` or DLL file in a specific location, an unprivileged user may be able to execute arbitrary code with SYSTEM privileges on a Windows system with the vulnerable Acronis software installed. See [DLL Search Order Hijacking](https://attack.mitre.org/techniques/T1574/001/) for more details. ### Solution #### Apply an update These vulnerabilities are addressed in Acronis True Image 2021 build 32010 ([release notes](https://www.acronis.com/en-us/support/updates/changes.html?p=42226)), Acronis Cyber Backup 12.5 build 16363 ([release notes](https://dl.managed-protection.com/u/backup/rn/12.5/user/en-US/AcronisBackup12.5_relnotes.htm)), and Acronis Cyber Protect 15 build 24600 ([release notes](https://dl.managed-protection.com/u/cyberprotect/rn/15/user/en-US/AcronisCyberProtect15_relnotes.htm)). ### Acknowledgements This vulnerability was reported by Will Dormann of the CERT/CC. Acronis also credits HackerOne researchers @adr, @mmg, @vanitas, @xnand with independently discovering and reporting the vulnerabilities. This document was written by Will Dormann.