Possible React Server Components Exploitation via Next-Action Header

ATT&CK techniques

Initial Access

Recon
Resource Dev
Initial Access
- T1190Exploit Public-Facing Application
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule detects inbound web requests carrying a Next-Action server action header together with crafted action parameter markers, the request shape used to trigger CVE-2025-55182 in React Server Components. Exploitation abuses the server action deserialization path to reach arbitrary command execution. Requests bearing this header alongside the action index syntax against a Next.js application warrant investigation for RCE attempts.

Reporting behind it

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Possible React Server Components Exploitation via Next-Action Header

Pivot detection · T1190 · 9 related

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