Detect Mirasvit Full Page Cache Warmer Deserialization RCE (CVE-2026-45247) in Sumo Logic CSE
Detects exploitation of CVE-2026-45247, a deserialization of untrusted data vulnerability in the Mirasvit Full Page Cache Warmer Magento extension. Successful exploitation allows remote attackers to execute arbitrary code by sending crafted serialized PHP objects to vulnerable endpoints. This CVE is listed in CISA KEV, indicating active exploitation in the wild.
MITRE ATT&CK
- Tactic
- Initial Access Execution Persistence
Sumo Detection Query
_sourceCategory=web/access OR _sourceCategory=iis OR _sourceCategory=apache
| where (%"cs-uri-stem" matches "*cache-warmer*" or %"cs-uri-stem" matches "*mirasvit*" or url matches "*cachewarmer*")
| where method in ("POST", "PUT")
| json field=_raw "bytes" as payload_bytes nodrop
| json field=_raw "cs-bytes" as cs_bytes nodrop
| eval payload_size = coalesce(payload_bytes, cs_bytes, 0)
| eval has_serialized_marker = if (matches(_raw, ".*O:[0-9]+:.*|.*rO0.*|.*YTo.*|.*Tzo.*"), 1, 0)
| where payload_size > 1000 or has_serialized_marker = 1
| stats count as hits, first(_messagetime) as first_seen, last(_messagetime) as last_seen, values(status) as statuses by src_ip, _sourceHost, url
| sort by hits descIdentifies POST/PUT requests to Mirasvit Full Page Cache Warmer URLs containing serialized PHP object patterns or large payloads that may represent deserialization exploit attempts.
Data Sources
Required Tables
False Positives & Tuning
- Legitimate cache warming automation that sends large POST payloads
- Third-party Magento SEO or performance tools accessing warmer endpoints
- Internal monitoring agents performing health checks via POST
- CDN origin pull requests that include sizeable payloads to cache warmer paths
Other platforms for CVE-2026-45247
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 1Simulate Deserialization Probe to Cache Warmer Endpoint
Expected signal: POST request to /mirasvit/cachewarmer/collect visible in web access logs with payload containing 'O:8:' serialization marker; HTTP response code logged
- Test 2PHP Deserialization Gadget Chain Simulation (Lab)
Expected signal: PHP CLI process spawned with command-line containing unserialize() — visible in auditd execve records or CrowdStrike process telemetry
- Test 3Web Shell Drop Simulation Following Deserialization RCE
Expected signal: File creation event in /var/www/html/pub/ for a .php file by the web server user (www-data or nginx); auditd CREATE record or Falcon sensor file event
Unlock Pro Content
Get the full detection package for CVE-2026-45247 including response playbook, investigation guide, and atomic red team tests.