CVE-2021-32706Public exploitNetwork attack vector

Authenticated command execution via unescaped wildcard validation

Published Aug 4, 2021 · Updated Aug 3, 2024

Command injection in Pi-hole Web Interface before 5.5.1 allows remote authenticated users to execute commands through API settings. The validDomainWildcard preg_match in client and domain validation leaves one period unescaped, so a crafted shell metacharacter reaches pihole_execute and is written to /etc/pihole/setupVars.conf. An authenticated administrative session must save the payload and invoke the gravity update, which sources the file and executes commands with root privileges.

CVSS severity7.6
High
EPSS probability60.18%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in Pi-hole Web Interface before 5.5.1 allows remote authenticated users to execute commands through API settings. The validDomainWildcard preg_match in client and domain validation leaves one period unescaped, so a crafted shell metacharacter reaches pihole_execute and is written to /etc/pihole/setupVars.conf. An authenticated administrative session must save the payload and invoke the gravity update, which sources the file and executes commands with root privileges.

The record

CVE
CVE-2021-32706
Published
Aug 4, 2021
Updated
Aug 3, 2024
Vendor
Pi-hole
Product
Pi-hole Web Interface
Classifications
CWE-94, T1059.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 4, 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?

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

  1. Affected versionversion=< 5.5.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Pi-hole · Pi-hole Web Interfaceversion=< 5.5.1

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P
7.6GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-94Improper Control of Generation of Code ('Code Injection')
T1059.004Unix Shell

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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