CVE-2021-27231Public exploitNetwork attack vector

Service spoofing via unchecked subdomain ownership

Published Feb 16, 2021 · Updated Aug 3, 2024

Improper authorization in Hestia Control Panel 1.3.5 and earlier allows remote authenticated users to hijack customer subdomains. The Add Web Domain form fails to verify that a requested subdomain belongs to another account before creating its web and DNS configuration. Exploitation requires two customers on the same shared server and a victim domain using that server's DNS; the attacker can spoof web or mail services and capture credentials.

CVSS severity5.4
Medium
EPSS probability1.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Hestia Control Panel 1.3.5 and earlier allows remote authenticated users to hijack customer subdomains. The Add Web Domain form fails to verify that a requested subdomain belongs to another account before creating its web and DNS configuration. Exploitation requires two customers on the same shared server and a victim domain using that server's DNS; the attacker can spoof web or mail services and capture credentials.

The record

CVE
CVE-2021-27231
Published
Feb 16, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1584.001
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 16, 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 privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1584.001Domains

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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