CVE-2026-33403Public exploitNetwork attack vector

Credential phishing via unescaped taillog parameter

Published Apr 6, 2026 · Updated Apr 6, 2026

DOM-based XSS in Pi-hole Web Interface 6.0 through 6.4.1 allows remote attackers to inject HTML through a crafted taillog URL. The taillog.js error path writes a rejected file parameter into innerHTML without escaping, while CSP omits form-action. A logged-in administrator must open the link; injected forms can capture the administrator password and permit DNS configuration changes.

CVSS severity6.1
Medium
EPSS probability0.19%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

DOM-based XSS in Pi-hole Web Interface 6.0 through 6.4.1 allows remote attackers to inject HTML through a crafted taillog URL. The taillog.js error path writes a rejected file parameter into innerHTML without escaping, while CSP omits form-action. A logged-in administrator must open the link; injected forms can capture the administrator password and permit DNS configuration changes.

The record

CVE
CVE-2026-33403
Published
Apr 6, 2026
Updated
Apr 6, 2026
Vendor
Pi-hole
Product
Pi-hole Web Interface
Classifications
CWE-79, T1056.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 6, 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, < 6.5

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Pi-hole · Pi-hole Web Interfaceversion=>= 6.0, < 6.5

Published CVSS scores

6.1GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1056.003Web Portal Capture

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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