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TI-2021-19106 Aliases CVE-2021-43040GHSA-4r5f-vh76-jqxp

An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5.

Priority MEDIUM 42Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.01827 78th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kaseya:unitrends_backup:*:*:*:*:*:*:*:*10.0 to before 10.5.5VulnerableKaseya
  • cpe:2.3:a:kaseya:unitrends_backup:*:*:*:*:*:*:*:* Versions 10.0 to before 10.5.5 Vulnerable ·Kaseya

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-43040
  2. 2026-10-03 Alias added: GHSA-4r5f-vh76-jqxp

References

Exploit 2

Advisory 1

  • TI-2017-09213 It was discovered that the api/storage web interface in Unitrends Backup (UB) before… CVSS 3.1CRITICAL 9.8
  • TI-2017-09212 It was discovered that the bpserverd proprietary protocol in Unitrends Backup (UB) before… CVSS 3.1CRITICAL 9.8
  • TI-2018-04653 It was discovered that the Unitrends Backup (UB) before 10.1.0 user interface was exposed… CVSS 3.0CRITICAL 9.8
  • TI-2017-09214 It was discovered that an issue in the session logic in Unitrends Backup (UB) before… CVSS 3.0HIGH 8.8
  • TI-2021-19099 An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. CVSS 3.1CRITICAL 9.8
  • TI-2021-19101 An issue was discovered in Kaseya Unitrends Backup Appliance before 10.5.5. CVSS 3.1CRITICAL 9.8
See all 16 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences