CVE-2021-43033
9.8
CRITICAL · CVSS 3.1 · EPSS 6.2% (pctl 93)
In your normal cycle
Critical by CVSS (9.8), but no sign of active exploitation.
Description
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. Multiple functions in the bpserverd daemon were vulnerable to arbitrary remote code execution as root. The vulnerability was caused by untrusted input (received by the server) being passed to system calls.
Scoring
| CVSS | 9.8 (CRITICAL, v3.1) |
|---|---|
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| EPSS | 6.19% — more likely to be exploited than 93% of all CVEs |
| Weakness | CWE-78 |
| On CISA KEV | no |
| Public exploit | none known |
| Published | 2021-12-06 |
| Last modified | 2026-06-17 |
Affected (1)
| Vendor | Product |
|---|---|
| kaseya | unitrends backup |
References
- https://helpdesk.kaseya.com/hc/en-gb/articles/4412762258961
- https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-1
- https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-2
- https://helpdesk.kaseya.com/hc/en-gb/articles/4412762258961
- https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-1
- https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-2
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