Node2Shell

• Large HTTP POST Request Resulting in Server Error :
  network Web Application None version:2
  This analytic detects HTTP POST requests with a body of at least one megabyte that receive an HTTP 500 response or cause a server crash. Large failed uploads can indicate attempts to trigger resource exhaustion or exploit vulnerable request handling, including behavior associated with PHP2Shell, but require investigation with related web and application logs.


• Linux Auditd Service Crash and Restart Burst :
  endpoint Endpoint None version:1
  This analytic detects repeated Linux process crash events followed by repeated successful executions of the same executable on the same host within 10 seconds. A rapid crash and restart pattern in a service process can indicate exploitation attempts or unstable application behavior and should be correlated with network and application telemetry.


• Linux Auditd Process Image Change Under Same PID :
  endpoint Endpoint None version:1
  This analytic detects a successful Linux execve event where a PID changes executable image under the same parent after the prior image has been active for at least one second and no more than 60 seconds. A delayed image change in an existing process can indicate execution following exploitation and should be investigated with related endpoint and network activity.


• Linux Suspicious React or Next.js Child Process :
  endpoint Endpoint None version:5
  This analytic detects Linux processes such as sh, bash, and common Linux LOLBINs being spawned by React or Next.js application servers. In the context of CVE-2025-55182 / React2Shell / CVE-2025-66478 for Next.js, successful exploitation can lead to arbitrary JavaScript execution on the server, which in turn is commonly used to invoke Node's child_process APIs (for example child_process.execSync) to run OS-level commands. Public proof-of-concept payloads and observed in-the-wild exploit traffic show patterns where the vulnerable React Server Components handler triggers process.mainModule.require('child_process').execSync() to execute binaries such as ping, curl, or arbitrary shells on the underlying host. This detection focuses on suspicious child processes where a Next/React server process spawns an uncommon process. Such activity might be a strong indicator of exploitation of the aforementioned vulnerability.