CVE-2021-24481Public exploitNetwork attack vector

Stored XSS via unescaped Allowed hosts setting

Published Aug 2, 2021 · Updated Aug 3, 2024

Stored XSS in Simon Fransson Any Hostname 1.0.6 and earlier allows remote authenticated users to execute script in an administrator's browser. The plugin saves the Allowed hosts option without sanitizing it and renders the value into the settings-page textarea without output escaping. An Administrator must submit the payload and a user must load the affected settings view, limiting exposure to authenticated administrative workflows.

CVSS severity4.8
Medium
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Simon Fransson Any Hostname 1.0.6 and earlier allows remote authenticated users to execute script in an administrator's browser. The plugin saves the Allowed hosts option without sanitizing it and renders the value into the settings-page textarea without output escaping. An Administrator must submit the payload and a user must load the affected settings view, limiting exposure to authenticated administrative workflows.

The record

CVE
CVE-2021-24481
Published
Aug 2, 2021
Updated
Aug 3, 2024
Vendor
Simon Fransson
Product
Any Hostname
Classifications
CWE-79, T1203
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 2, 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=1.0.6 <=1.0.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Simon Fransson · Any Hostnameversion=1.0.6 <=1.0.6

Published CVSS scores

4.8NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
3.5NVDAV: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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