CVE-2021-47871Public exploitNetwork attack vectorHinoki check available

Authenticated arbitrary file write via API path control

Published Jan 21, 2026 · Updated Jan 21, 2026

Arbitrary file write in Hestia Control Panel 1.3.2 allows remote authenticated users to write server files through its API. The API dispatches v-make-tmp-file with user-controlled content and destination path, including /home/admin/.ssh/authorized_keys. A valid API key is required, and the CNA separately lists 1.3.3 as affected despite the published exploit identifying versions before 1.3.3.

CVSS severity8.6
High
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkAvailable
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Summary

What happened

Arbitrary file write in Hestia Control Panel 1.3.2 allows remote authenticated users to write server files through its API. The API dispatches v-make-tmp-file with user-controlled content and destination path, including /home/admin/.ssh/authorized_keys. A valid API key is required, and the CNA separately lists 1.3.3 as affected despite the published exploit identifying versions before 1.3.3.

The record

CVE
CVE-2021-47871
Published
Jan 21, 2026
Updated
Jan 21, 2026
Vendor
Hestia Control Panel
Product
Hestia Control Panel
Classifications
CWE-73, T1098.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.3.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Hestia Control Panel · Hestia Control Panelversion=1.3.3

Published CVSS scores

8.6VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8VulnCheckCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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

CWE-73External Control of File Name or Path
T1098.004SSH Authorized Keys

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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