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The requirement that, when deriving a Program Derived Address (PDA), a program always use the canonical bump — the highest bump value (starting from 255 and decrementing) for which find_program_address returns a valid off-curve point — rather than accepting an arbitrary bump supplied by the caller. If a program stores and re-uses a non-canonical bump, an attacker can create a different PDA (with a different canonical bump) that happens to match a seed set the program trusts, or can derive valid PDAs outside the expected namespace. Anchor's seeds and bump constraints enforce canonicalization by calling find_program_address internally and asserting the provided bump matches; storing the canonical bump in the account at init time (instead of rediscovering it) is the recommended gas-efficient pattern.

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Bump Seed Canonicalization (bump-seed-canonicalization)
Category: Security
Definition: The requirement that, when deriving a Program Derived Address (PDA), a program always use the canonical bump — the highest bump value (starting from 255 and decrementing) for which find_program_address returns a valid off-curve point — rather than accepting an arbitrary bump supplied by the caller. If a program stores and re-uses a non-canonical bump, an attacker can create a different PDA (with a different canonical bump) that happens to match a seed set the program trusts, or can derive valid PDAs outside the expected namespace. Anchor's seeds and bump constraints enforce canonicalization by calling find_program_address internally and asserting the provided bump matches; storing the canonical bump in the account at init time (instead of rediscovering it) is the recommended gas-efficient pattern.
Related: Bump Seed, Program Derived Address (PDA)

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Branch

Bump Seed

A single byte (255 down to 0) appended to PDA seeds to push the derived address off the Ed25519 curve. find_program_address tries bump=255 first and decrements until finding a valid PDA. The first valid bump found is the canonical bump. Always store and reuse the canonical bump to avoid security issues.

Seeds

Open term

Branch

Program Derived Address (PDA)

An account address derived deterministically from a program ID and a set of seeds, with no corresponding private key. PDAs are created by finding a pubkey that does NOT lie on the Ed25519 curve (using a bump seed). Since there's no private key, only the deriving program can sign for the PDA via invoke_signed, making PDAs ideal for program-controlled state.

find_program_address

Open term

Next concepts to explore

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Programming Model

Bump Seed

A single byte (255 down to 0) appended to PDA seeds to push the derived address off the Ed25519 curve. find_program_address tries bump=255 first and decrements until finding a valid PDA. The first valid bump found is the canonical bump. Always store and reuse the canonical bump to avoid security issues.

Open term

Programming Model

Program Derived Address (PDA)

An account address derived deterministically from a program ID and a set of seeds, with no corresponding private key. PDAs are created by finding a pubkey that does NOT lie on the Ed25519 curve (using a bump seed). Since there's no private key, only the deriving program can sign for the PDA via invoke_signed, making PDAs ideal for program-controlled state.

Open term

Security

Checked Math

A family of Rust arithmetic methods — including checked_add, checked_sub, checked_mul, checked_div, and their saturating_* counterparts — that return an Option<T> (None on overflow/underflow) instead of silently wrapping, allowing Solana programs to propagate an error rather than continue with corrupted values. Because Rust's default integer arithmetic panics on overflow only in debug builds and wraps silently in release builds (the mode used for on-chain deployments), all financial and security-sensitive arithmetic in Solana programs should use these methods. Anchor's declare_program! macro and many audit checklists explicitly require checked math on all token amount calculations.

Open term

Security

Bug Bounty

Security program offering financial rewards to researchers who find and responsibly report vulnerabilities. The Solana Foundation maintains a bug bounty program on Immunefi with rewards up to $1M for critical validator/runtime bugs. Major protocols like Jupiter, Marinade, and Jito also run independent bounty programs.

Open term

Related terms

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Programming Modelbump

Bump Seed

A single byte (255 down to 0) appended to PDA seeds to push the derived address off the Ed25519 curve. find_program_address tries bump=255 first and decrements until finding a valid PDA. The first valid bump found is the canonical bump. Always store and reuse the canonical bump to avoid security issues.

Open term

Programming Modelpda

Program Derived Address (PDA)

An account address derived deterministically from a program ID and a set of seeds, with no corresponding private key. PDAs are created by finding a pubkey that does NOT lie on the Ed25519 curve (using a bump seed). Since there's no private key, only the deriving program can sign for the PDA via invoke_signed, making PDAs ideal for program-controlled state.

Open term

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Security

Missing Signer Check

A vulnerability where a program accepts an account in a privileged role (e.g., admin, authority, payer) without verifying that the account actually signed the transaction, allowing any caller to impersonate that authority by simply passing the target pubkey as an instruction account. In native Solana programs, the check requires asserting account.is_signer == true; in Anchor, the Signer<'info> type enforces this automatically. Exploitation lets an attacker bypass all access control gated on authority equality checks, making it one of the most critical and commonly audited vulnerabilities in Solana programs.

Open term

Security

Missing Owner Check

A vulnerability where a program deserializes and trusts account data without first confirming that the account is owned by the expected program, allowing an attacker to substitute a maliciously crafted account owned by a different program whose byte layout happens to satisfy the deserialization. On Solana, every account stores a 32-byte owner field set to the program that created it; native programs must assert account.owner == &expected_program_id, while Anchor's Account<'info, T> wrapper performs this check automatically. Failure to validate ownership can lead to complete auth bypass if an attacker can construct a fake account whose data parses into a struct with elevated privileges.

Open term

Security

Arbitrary CPI

A vulnerability where a program accepts an arbitrary program account from the caller and invokes it via Cross-Program Invocation (CPI) without verifying it matches a known, trusted program ID, effectively letting an attacker substitute a malicious program that executes under the victim program's authority or manipulates accounts the victim program passes to it. A common pattern is accepting a token_program account without checking it equals spl_token::ID, so the attacker passes a lookalike program that records or drains account data. Prevention requires hard-coding or explicitly checking the program ID before every CPI call.

Open term

Security

PDA Substitution Attack

A vulnerability where a program derives a PDA internally but accepts an externally supplied account as that PDA without re-deriving and comparing the address, allowing an attacker to pass a different PDA (derived from attacker-controlled seeds) that the program will treat as legitimate. Because PDAs are deterministic, the only way to guarantee account identity is to call Pubkey::find_program_address (or equivalent) with the expected seeds inside the program and assert the result equals the supplied key. Anchor's seeds and bump constraints on the Account type automate this re-derivation and equality check.

Open term