CISA KEV · Known exploitedCritical

CVE-2026-56290

joomlack.fr JoomlaCK.fr Page Builder CK extension for Joomla, page builder ck

Joomla Extension - joomlack.fr - Unauthenticated file upload in Page Builder CK extension < 3.6.0 - The Joomla extension Page Builder CK is vulnerable to an unauthenticated arbitrary file upload that allows uploading executable files and leads to full RCE.

CVSS
10
EPSS
2.91%
85.5% percentile
CISA KEV
Listed
Published
2026.06.30
PRIORITY ASSESSMENT

Immediate review

CISA has listed this vulnerability in the Known Exploited Vulnerabilities catalog.

Known exploitationConfirmed by CISA KEV
Exploit probability2.91%
Technical severityCVSS 10

Vulnerability overview

Joomla Extension - joomlack.fr - Unauthenticated file upload in Page Builder CK extension < 3.6.0 - The Joomla extension Page Builder CK is vulnerable to an unauthenticated arbitrary file upload that allows uploading executable files and leads to full RCE.

Affected product and versions

Product
joomlack.fr JoomlaCK.fr Page Builder CK extension for Joomla, page builder ck
Affected versions
>= 1.0-3.6.0, < 3.6.0
Fixed versions
3.6.0

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
CISA required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Due date: 2026.07.10
  1. 1
    Identify

    Confirm that joomlack.fr JoomlaCK.fr Page Builder CK extension for Joomla, page builder ck and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:A/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:X/V:X/RE:X/U:Red
CWE
CWE-284, CWE-434
KEV added
2026.07.07
Ransomware use
미확인