CVE-2026-35521Public exploitNetwork attack vector

Authenticated command execution via dhcp.hosts newline injection

Published Apr 7, 2026 · Updated Apr 7, 2026

Command injection in Pi-hole FTL 6.0 through 6.5 allows remote authenticated users to execute commands through the administrative API. The dhcp.hosts handler uses validate_stub, which always returns true, before fprintf writes unsanitized values into dnsmasq configuration. Administrative API access and a resolver restart let injected leasefile-ro and dhcp-script directives reach dnsmasq's popen path and run commands as the pihole user.

CVSS severity8.8
High
EPSS probability0.69%
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 FTL 6.0 through 6.5 allows remote authenticated users to execute commands through the administrative API. The dhcp.hosts handler uses validate_stub, which always returns true, before fprintf writes unsanitized values into dnsmasq configuration. Administrative API access and a resolver restart let injected leasefile-ro and dhcp-script directives reach dnsmasq's popen path and run commands as the pihole user.

The record

CVE
CVE-2026-35521
Published
Apr 7, 2026
Updated
Apr 7, 2026
Vendor
Pi-hole
Product
Pi-hole FTL
Classifications
CWE-78, CWE-20, CWE-93, T1059.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 7, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 7, 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=>= 6.0, < 6.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Pi-hole · Pi-hole FTLversion=>= 6.0, < 6.6

Published CVSS scores

8.8GitHub, Inc.CVSS: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-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CWE-20Improper Input Validation
CWE-93Improper Neutralization of CRLF Sequences ('CRLF 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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