CVE-2021-43034 json
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5.
published 2021-12-06 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-29988
- cvss
- 7.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.5%
- EPSS 0.5% chance of exploitation in 30 days, percentile 39%
- public exploits
- 0
- none known
Summary
An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. A world writable file allowed local users to execute arbitrary code as the user apache, leading to privilege escalation.
Patch / fix
- kaseya unitrends_backup 10.5.5
Exploit prediction
0.45% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- cyberonesecurity.com https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-1 referenced PoC, tagged "exploit" by a source, unverified
- cyberonesecurity.com https://www.cyberonesecurity.com/blog/exploiting-kaseya-unitrends-backup-appliance-part-2 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 7.8 | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 4.6 | AV:L/AC:L/Au:N/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-732 Incorrect Permission Assignment for Critical Resource
References
-
cyberonesecurity.com
/blog/exploiting-kaseya-unitrends-backup-appliance-part-1
exploit, third-party-advisory
-
cyberonesecurity.com
/blog/exploiting-kaseya-unitrends-backup-appliance-part-2
exploit, third-party-advisory
-
helpdesk.kaseya.com
/hc/en-gb/articles/4412762258961
vendor-advisory
Sources
- CVE List CVE-2021-43034
- NVD CVE-2021-43034
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