Malicious Langflow Build Public Temp RCE Access via Webserver

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 POST requests to the Langflow build_public_tmp flow endpoint exploited by CVE-2026-55255 to achieve unauthenticated remote code execution. Attackers chain an IDOR on the responses endpoint with this build path to run arbitrary flows. Requests to this endpoint from untrusted sources indicate active exploitation of the exposed Langflow instance.

Reporting behind it

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Malicious Langflow Build Public Temp RCE Access via Webserver

Pivot detection · T1190 · 9 related

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