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# Reverse engineering - light up the server

## **Solution**

### **After Analyzing the server in IDA Pro and Flare CAPA**

<figure><img src="/files/HWrUxmJBgsDklFd5wDFs" alt=""><figcaption><p>Flare capa</p></figcaption></figure>

**The rule detected a regex as obfuscated stack strings**

```
/^([a-z]?[^a-e,g-z])la[g]{(h)0(s)t_\2(e)4d\4(r([_]?[^a-z]))(!)n((j(3))cti0)n(_)1s\6{1}5up3\5c3wl}$/gm
```

### Finding a match string via regex101

<figure><img src="/files/j8sN6EolnckITeZRntuh" alt=""><figcaption><p>Match flag</p></figcaption></figure>

### The Flag

```
flag{h0st_he4der_!nj3cti0n_1s_5up3r_c3wl}
```