Detect CVE-2026-48908 - JoomShaper SP Page Builder Unrestricted File Upload in CrowdStrike LogScale
Detects exploitation of CVE-2026-48908, an unrestricted file upload vulnerability (CWE-434) in JoomShaper SP Page Builder for Joomla. Attackers can upload files with dangerous types (e.g., PHP webshells) through the page builder interface, leading to remote code execution. This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog.
MITRE ATT&CK
- Tactic
- Initial Access Execution Persistence
LogScale Detection Query
#event_simpleName IN ("HttpRequest", "NetworkConnectIP4", "WriteFile", "CreateFile")
| filter HttpMethod = "POST"
| filter match(TargetUrl, "(?i)/components/com_sppagebuilder")
| filter HttpStatusCode IN ("200", "201", "202")
| eval file_path = coalesce(FilePath, TargetFilename, "")
| eval dangerous_upload =
if(match(TargetUrl, "(?i)\\.(php\\d?|phtml|phar|asp|aspx|jsp|cgi|pl|py|sh|bash)"), 1,
if(match(file_path, "(?i)\\.(php\\d?|phtml|phar|asp|aspx|jsp)"), 1, 0))
| filter dangerous_upload = 1
| eval cve = "CVE-2026-48908"
| eval risk_score = 90
| eval mitre = "T1190,T1505.003"
| groupBy([SourceIP, TargetUrl, HttpStatusCode, file_path, cve, risk_score], function=[count(aid, as=event_count), min(timestamp, as=first_seen), max(timestamp, as=last_seen)])
| sort -event_countCrowdStrike Falcon LogScale query correlating HTTP POST events to SP Page Builder endpoints with dangerous file extensions, detecting CVE-2026-48908 unrestricted upload exploitation.
Data Sources
Required Tables
False Positives & Tuning
- Falcon sensor telemetry gaps causing legitimate POST requests to appear suspicious without full context
- Joomla CLI maintenance tasks writing PHP files to component directories outside web context
- Web application deployments where PHP files are copied to component paths by DevOps pipelines
Other platforms for CVE-2026-48908
Testing Methodology
Validate this detection against 3 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Unauthenticated PHP Webshell Upload via SP Page Builder
Expected signal: Web server access log entry: POST /index.php?option=com_sppagebuilder&task=file.upload HTTP/1.1 200; multipart/form-data body containing filename=shell.php with PHP content
- Test 2Double Extension Bypass Upload Attempt
Expected signal: POST request to SP Page Builder upload endpoint with filename containing double extension (.php.jpg); web server logs showing 200 response and file write event to upload directory
- Test 3Webshell Execution Verification Post-Upload
Expected signal: Web server access log entries: GET /images/shell.php HTTP/1.1 200; process execution events showing php-fpm or apache spawning child processes (id, hostname, uname); potential outbound network connections from web server process
References (4)
- https://extensions.joomla.org/extension/sp-page-builder/
- https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk
- https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk
- https://nvd.nist.gov/vuln/detail/CVE-2026-48908
Unlock Pro Content
Get the full detection package for CVE-2026-48908 including response playbook, investigation guide, and atomic red team tests.