CVE-2023-4451Public exploitNetwork attack vector

Browser script execution via unsanitized installer space parameter

Published Aug 20, 2023 · Updated Feb 13, 2026

Reflected XSS in Cockpit CMS before 2.6.4 allows remote attackers to execute JavaScript through a crafted installer URL. The install/index.php handler assigns the space query parameter to APP_SPACE without filtering, allowing injected markup to reach the installation page. A victim must open the crafted URL while the installer is reachable; the injected script then runs in that victim's browser under the Cockpit origin.

CVSS severity6.1
Medium
EPSS probability2.50%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Cockpit CMS before 2.6.4 allows remote attackers to execute JavaScript through a crafted installer URL. The install/index.php handler assigns the space query parameter to APP_SPACE without filtering, allowing injected markup to reach the installation page. A victim must open the crafted URL while the installer is reachable; the injected script then runs in that victim's browser under the Cockpit origin.

The record

CVE
CVE-2023-4451
Published
Aug 20, 2023
Updated
Feb 13, 2026
Vendor
Cockpit HQ
Product
Cockpit CMS
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 20, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 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=0 <2.6.4
  2. Affected versionversion=unspecified <2.6.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Cockpit HQ · Cockpit CMSversion=0 <2.6.4; version=unspecified <2.6.4

Published CVSS scores

6.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
6.1huntr.devCVSS:3.0/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.

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
Privilegesunauthenticated
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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