CVE-2026-56290

Joomlack Page Builder: Improper Access Control

As of , CVE-2026-56290 in Joomlack Page Builder is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch now.

Exploited
Yes: CISA listed it on 7 July 2026
US federal deadline
10 July 20263 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
Forensic triage
Required by CISA under BOD 26-04Agencies must also look for signs that attackers already got in.
EPSS score
0.31Higher than 98% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
Public exploit
1 Exploit-DB entry
Fix
Vendor advice: www.joomlack.frLinks below, from CISA's entry.

What CISA says to do

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.

CISA's required action

What the flaw is

Joomlack Page Builder contains an improper access control vulnerability that could allow for remote code execution via unauthenticated arbitrary file upload.

CISA's description

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.

The CVE record's description, from Joomla

CVE published
29 June 2026
Assigned by
Joomla
CVSS
10.0 Critical (CVSS 4.0, from the CNA)
CWE-434
Unrestricted Upload of File with Dangerous Type
CWE-284
Improper Access Control
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. Exploit-DB published an exploit (EDB-ID 52626).
  4. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

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