CVE-2021-43034

Local privilege escalation via world-writable file

Published Dec 6, 2021 · Updated Aug 4, 2024

Local privilege escalation in Kaseya Unitrends Backup Appliance before 10.5.5 allows local users to execute arbitrary code as apache. The appliance assigns world-write permission to a file whose contents are executed under the apache account, allowing replacement with attacker-controlled code. Exploitation requires local appliance access; public sources identify neither the affected file nor a path from apache to root.

CVSS severity7.8
High
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Local privilege escalation in Kaseya Unitrends Backup Appliance before 10.5.5 allows local users to execute arbitrary code as apache. The appliance assigns world-write permission to a file whose contents are executed under the apache account, allowing replacement with attacker-controlled code. Exploitation requires local appliance access; public sources identify neither the affected file nor a path from apache to root.

The record

CVE
CVE-2021-43034
Published
Dec 6, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-732
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Dec 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.8NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
4.6NVDAV:L/AC:L/Au:N/C:P/I:P/A:P

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-732Incorrect Permission Assignment for Critical Resource

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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