flawopen.com/Simulators
Interactive Vulnerability Simulators
Theoretical vulnerability write-ups often fail to convey the dynamic runtime interactions that cause software to fail. Our interactive visualizers allow you to scrub through socket byte streams, inspect memory arenas step-by-step, and manipulate exploit parameters in real time — completely safe, client-side, and zero-install.
HTTP Request Smuggling (CL.TE & TE.CL Desynchronization)
Visualize how conflicting Content-Length and Transfer-Encoding: chunked headers cause frontend reverse proxies and backend servers to interpret request boundaries differently. Watch how orphaned bytes in the persistent TCP socket prepend to subsequent requests to poison innocent user sessions.
Heap Use-After-Free (UAF) & Chunk Re-allocation Visualizer
Step through virtual memory allocation, slab deallocation, and dangling pointer retention. Watch how an attacker sprays crafted heap structures into the freed chunk slot, hijacking function pointers when the original dangling pointer is subsequently dereferenced for kernel privilege escalation.
OpenSSL Heartbleed Buffer Overread Visualizer
Step through TLS Heartbeat record parsing, unvalidated payload length handling, and adjacent server heap memory overreads. Watch how missing packet bounds checks copy private SSL keys, user session tokens, and passwords straight back to an attacker.
Live In-Browser Sandbox Preview
Try the interactive HTTP Request Smuggling engine directly below:
🛡️ Safe Client-Side Execution Guarantee
All simulators on flawopen.com execute entirely within your browser's isolated JavaScript virtual machine. They contain mathematical models and visual state machines of software parsers; no live exploits or native binaries are executed on your machine or on our servers.