CVE-2021-41175Public exploitNetwork attack vector

Stored script execution via unescaped client address

Published Oct 26, 2021 · Updated Aug 4, 2024

Stored cross-site scripting in Pi-hole Web Interface before 5.8 allows remote authenticated users to execute script in an administrator's browser. The add_client path accepts an ip field containing markup, stores it as a client, and renders the value without HTML encoding through groups.php and groups-clients.js. A valid administrative session and CSRF token are required to add the crafted client, and script execution depends on an administrator loading the affected management content.

CVSS severity7.3
High
EPSS probability0.90%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Pi-hole Web Interface before 5.8 allows remote authenticated users to execute script in an administrator's browser. The add_client path accepts an ip field containing markup, stores it as a client, and renders the value without HTML encoding through groups.php and groups-clients.js. A valid administrative session and CSRF token are required to add the crafted client, and script execution depends on an administrator loading the affected management content.

The record

CVE
CVE-2021-41175
Published
Oct 26, 2021
Updated
Aug 4, 2024
Vendor
Pi-hole
Product
Pi-hole Web Interface
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=< 5.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Pi-hole · Pi-hole Web Interfaceversion=< 5.8

Published CVSS scores

7.3GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/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.

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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript

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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