CVE-2026-87902

WordPress Core

score 80Known exploited · added 2026-09-25Public PoC ×26Nuclei template

Summary

WordPress Core Remote File Inclusion Vulnerability

WordPress Core contains a remote file inclusion vulnerability which could allow an unauthenticated attacker to make page-template resolution include a chosen readable local `.php` file outside the active theme directories, leading to remote code execution.

Published 2026-09-25 · first seen here 2026-10-10

CISA required action (due 2026-09-28): 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.

Analysis & write-ups

No technical write-up from a research team yet. Contact Zero checks Unit 42, Google/Mandiant, Microsoft, Talos, CrowdStrike, Rapid7, watchTowr and others several times a day, plus NVD and CISA reference links.

Exploit availability

Public exploit code lowers the bar for attackers, so prioritise patching and hunting. These repositories are unverified. Fake PoCs that contain malware are common, so never run them outside an isolated lab.

Nuclei detection template · ProjectDiscovery
ressl/cve-2026-87902-poc · ★38 · created 2026-09-22
abraxas/CVE-2026-87902 · ★35 · created 2026-09-22
dinosn/cve-2026-87902-wordpress-lfi-lab · ★13 · created 2026-09-23
tc4dy/CVE-2026-87902-Toolkit · ★11 · created 2026-09-23
vulpecuna/CVE-2026-87902 · ★9 · created 2026-09-22
+21 more

Where it shows in your logs

CISA requires forensic triage for this CVE (BOD 26-04): check affected systems for signs of compromise, don't just patch.

Server or web application · Command or code injection (remote code execution) medium confidence

What to look for

Shell metacharacters or encoded payloads in request parameters (; | ` $( %0a)
The vulnerable process spawning shells, then downloaders (curl, wget, certutil, Invoke-WebRequest)
The application's process (w3wp.exe, java, tomcat, node, php-fpm, httpd, python) starting shells or LOLBins (cmd, powershell, sh, bash, curl, wget, certutil)
New script files in web roots (.jsp, .aspx, .php): a web shell
Requests to unusual URLs on the application from internet IPs right before any of the above
Outbound connections from the server to new external IPs

Data sources

Web server and WAF logs · ATT&CK DS0015 Application Log Content

Sentinel: W3CIISLogAppServiceHTTPLogsAzureDiagnostics (Application Gateway / Front Door WAF)_Im_WebSession
Splunk: Web.Webms:iis:autoaccess_combinedWAF / proxy sourcetypes
CrowdStrike: Falcon Next-Gen SIEM: third-party web / WAF / proxy logs

Process creation · ATT&CK DS0009 Process Creation

Sentinel: DeviceProcessEventsSecurityEvent (4688)Sysmon Event ID 1_Im_ProcessCreate
Splunk: Endpoint.ProcessesXmlWinEventLog:Microsoft-Windows-Sysmon/OperationalWinEventLog:Security (4688)
CrowdStrike: ProcessRollup2SyntheticProcessRollup2

File creation · ATT&CK DS0022 File Creation

Sentinel: DeviceFileEventsSysmon Event ID 11_Im_FileEvent
Splunk: Endpoint.FilesystemSysmon Event ID 11
CrowdStrike: NewExecutableWrittenNewScriptWritten*FileWritten events

Network connections · ATT&CK DS0029 Network Connection Creation / Network Traffic Flow

Sentinel: DeviceNetworkEventsCommonSecurityLog (firewall)_Im_NetworkSession
Splunk: Network_Traffic.All_TrafficFirewall sourcetypes (pan:traffic, fortigate_traffic, cisco:asa)
CrowdStrike: NetworkConnectIP4NetworkReceiveAcceptIP4NetworkConnectIP6

A generic baseline worked out from the product type and weakness (CWE-98), not a detection. Check table and field names against your environment. Hunt queries for Sigma, Splunk, Sentinel and CrowdStrike are coming.

News & advisories

28th September – Threat Intelligence Report · Check Point Research