CVE-2021-43040
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged...
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged vaultServer could be leveraged to create arbitrary writable files, leading to privilege escalation.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged vaultServer could be leveraged to create arbitrary writable files, leading to privilege escalation.
- Record
CVE-2021-43040- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 6.5 Medium
AV:N/AC:L/Au:S/C:P/I:P/A:P - Updated
- 2026-11-02
CVE List No score
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged vaultServer could be leveraged to create arbitrary writable files, leading to privilege escalation.
- Record
CVE-2021-43040- Updated
- 2026-11-02
EUVDEUVD-2021-29994 No score
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged vaultServer could be leveraged to create arbitrary writable files, leading to privilege escalation.
- Record
EUVD-2021-29994- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-4r5f-vh76-jqxp
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged...
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. The privileged vaultServer could be leveraged to create arbitrary writable files, leading to privilege escalation.
- Record
GHSA-4r5f-vh76-jqxp- CVSS 3.1
- 8.8 High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-269
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-43040 is a high vulnerability (CVSS 8.8) in Kaseya Unitrends Backup, published December 6, 2021. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.83%, the 78th percentile. No source names a fixed version.