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# System prepended metadata

title: 'l15 Stall Investigation:'

---

# l15 Stall Investigation:

### Slot: 5278
- Van parent block: 5277
- Pan block Number: 4732
- Header Hash: 0xcbd44e37125c599ff218b966658d720665e1dfa9fd3db0230ad8743e754495d5
- Parent block number: 4731
- Parent Hash: 0xa137cb9c9a22f678994b82c09f31de79994222470c1a77dfc7c78268bb5d0bbc

### Slot: 5279
- Van parent block: 5278
- Pan block Number: 4733
- Header Hash: 0x0acf03ae123dc232e181d3273114b4fc1ae570f469c64655ccb7bc8c6b6aaa28
- Parent block number: 4732
- Parent Hash: 0xcbd44e37125c599ff218b966658d720665e1dfa9fd3db0230ad8743e754495d5

### Slot: 5280
- Van parent block: 5271
- Pan block Number: 4728
- Header Hash: 0xd5aa89dff5365a87d6ed489a58c4e9d570e90bce327c2d51449f9e9e2917f588
- Parent block number: 4727
- Parent Hash: 0xfccd8d44c6554f390556e7a6d48670fa13147dade6824993725bdb27868f7e01

:warning: **Re-org was orrcured here and reverted valid blocks from #5272 to #5279 and accept #5280 which was contained invalid pandora shard**

## Question
1. Why did fork choice rule of vanguard discard blocks from slot #5272 to #5279? 
2. There was not any checking for pandora sharding in block verification process. That's why every valid node excepted the malicious node's block in vanguard side.