Security readout for executives and security teams
Plain-English summary
A logged-in attacker with limited privileges may upload arbitrary files through vulnerable Page Builder CK installations and gain control of the Joomla server. Successful compromise could enable website takeover, data theft, malware deployment, and service disruption. Exposure is limited to sites using the affected extension, but the potential impact is severe.
Executive priority
Treat as an urgent remediation item for internet-facing sites using the extension. Identify affected systems immediately, reduce account and network exposure, and obtain definitive vendor upgrade guidance. Escalate incident review if suspicious uploads, file changes, or authenticated activity are found.
Technical view
CVE-2026-63048 is an improper file-upload control vulnerability, classified as CWE-434. It is remotely reachable, requires low privileges, needs no user interaction, and can lead to remote code execution. The supplied CVSS 4.0 score is 9.4. The source bundle conflicts on whether version 3.6.2 itself is affected.
Likely exposure
Internet-facing Joomla sites using Page Builder CK are the primary concern, especially where untrusted or compromised users hold extension-accessible accounts. Sites without this extension are not indicated as affected. Exact version exposure requires vendor clarification because the title says versions below 3.6.2, while the affected range includes 3.6.2.
Exploitation context
Authentication is required, but only low privileges are indicated. No user interaction or unusual attack complexity is required. The supplied record is not marked as KEV, and the cited material provides no evidence of active exploitation or a public exploit. Absence of such evidence does not establish that exploitation has not occurred.
Researcher notes
The main evidence gap is version-boundary ambiguity: the title states versions below 3.6.2, while structured affected data lists 1.0.0 through 3.6.2. The sources supplied do not identify a fixed release, detailed vulnerable endpoint, vendor advisory, or exploitation telemetry. Avoid declaring 3.6.2 safe until authoritative clarification appears.
Mitigation direction
- Check current joomlack.fr guidance for the corrected version and official remediation instructions.
- Prioritize upgrading once the vendor confirms which release resolves the vulnerability.
- Disable or restrict Page Builder CK where immediate remediation is unavailable and operationally acceptable.
- Review and revoke unnecessary Joomla accounts and extension permissions.
- Restrict administrative access to trusted networks where feasible.
Validation and detection
- Inventory Joomla sites and confirm whether Page Builder CK is installed.
- Record installed versions, treating 3.6.2 as uncertain until vendor clarification.
- Review extension and server logs for unexpected authenticated uploads or account activity.
- Inspect web-accessible directories for unauthorized or recently changed executable files.
- Confirm remediation against an official vendor advisory or updated CVE record.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-434: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupFile access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-63048 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.4 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H——JoomlaVulnerability scoring details
Base CVSS 4.0 score
9.4CriticalVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://www.joomlack.fr/CVE reference, Joomla · product
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Unrestricted Upload of File with Dangerous Type
Unrestricted Upload of File with Dangerous Type represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.