CVE-2021-30201Public exploitNetwork attack vector

Unauthenticated file disclosure via external entity resolution

Published Jul 9, 2021 · Updated Aug 3, 2024

XML external entity injection in Kaseya VSA before 9.5.6 allows remote attackers to read server-accessible files through its SOAP API. The /vsaWS/KaseyaWS.asmx PrimitiveResetPassword handler resolves attacker-supplied external entities and reflects resolved file content in verbose XML errors. No authentication or user interaction is required, and crafted entities can also force HTTP or HTTPS requests into systems reachable from the VSA server.

CVSS severity7.5
High
EPSS probability25.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

XML external entity injection in Kaseya VSA before 9.5.6 allows remote attackers to read server-accessible files through its SOAP API. The /vsaWS/KaseyaWS.asmx PrimitiveResetPassword handler resolves attacker-supplied external entities and reflects resolved file content in verbose XML errors. No authentication or user interaction is required, and crafted entities can also force HTTP or HTTPS requests into systems reachable from the VSA server.

The record

CVE
CVE-2021-30201
Published
Jul 9, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5MITRECVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

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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