critical Known exploitedREV. 01
CVE-2026-56290Page Builder CK for Joomla — unauthenticated upload to RCE
The Joomlack page builder extension for Joomla before 3.6.0 (Page Builder CK) lets anyone upload a file of any type, so an attacker can put an executable script on the site and run it, taking over the web server.
Read the risk
THE VITAL STATS- CVSS score
- 9.8/ 10 CVSS v3.1
- EPSS probability
- 31% Likelihood of exploitation
- Attack complexity
- Low Conditions needed to exploit
- Known exploited
- Yes — CISA KEV
- CVE published
- 2026-06-29
- Added to KEV
- 2026-07-07
- Exploit published
- Yes
- Confidence
- high
- Kill chain
- initial access
- MITRE ATT&CK
- T1190, T1505.003
- Severity
- critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attacker needsNetwork access to a Joomla site running the extension; no account needed.
Fixed inPage Builder CK 3.6.0
Behind the card
4 REFERENCES- 01CVE recordNVD recordnvd.nist.gov
- 02CISACISA Known Exploited Vulnerabilities catalogcisa.gov
- 03Vendor advisoryforum.joomlack.frforum.joomlack.fr
- 04Exploitmysites.gurumysites.guru
Field-level provenanceTRACE THE SOURCES +
Which source supports each field, when it was retrieved, and who extracted it.
| Fields | Source | Retrieved | Extractor | Confidence |
|---|---|---|---|---|
| cvss, exploitation.attack_complexity, exploitation.exploit_available, references, published_at | nvd.nist.gov | 2026-09-23 | scrty-crds-pipeline/0.1 | high |
| exploitation.known_exploited, exploitation.kev_added | cisa.gov | 2026-09-23 | scrty-crds-pipeline/0.1 | high |
| epss | api.first.org | 2026-09-23 | scrty-crds-pipeline/0.1 | high |
| title, summary, severity, remediation, mitre_attack, kill_chain, recommended_action, confidence, tags, exploitation.prerequisites | nvd.nist.gov | 2026-09-23 | claude-code | high |
Printing history
THE RECORD- r1Initial base card
First printing. This card has not been reprinted since publication.