Polygon PoS bridge: cross-chain bridges rating breakdown
Never exploited, cheap, and used by an enormous number of people who believe it is something it is not.
Never exploited, cheap, and used by an enormous number of people who believe it is something it is not.
How the score is built
Each criterion is scored 0–10 and weighted. The median column is the middle score across every entry in this ranking, so a row reads as a position rather than a number.
| Criterion | What we measured | Weight | Score | Category median | Rank | Weighted gap |
|---|---|---|---|---|---|---|
| Trust assumption | NO — despite the common belief is it a canonical rollup bridge · sourced · 2026-07-15 · source | 40% | 2 | 4 | 16 of 16 | -0.80 |
| The upgrade key | 0xFa7D2a996aC6350f4b56C043112Da0366a59b74c multisig address · sourced · 2026-07-15 · source | 15% | 1 | 3 | 16 of 16 | -0.30 |
| Incidents — and did users get paid | none to date exploits · sourced · 2026-07-15 | 25% | 9 | 9 | 7 of 16 | 0.00 |
| Audits and transparency | — | 10% | 5 | 5.5 | 9 of 16 | -0.05 |
| Cost and speed | — | 10% | 8 | 6 | 4 of 16 | +0.20 |
Measured 15 July 2026 · weights and method · decided by trust assumption, worth -0.80 points against the median
Trust assumption: 2/10
Not a label — a number. Who, exactly, can move the money if they collude or are compromised? A canonical rollup bridge answers "nobody: Ethereum itself verifies the withdrawal, and the seven-day window is the period in which fraud can be proven". An external committee answers with a threshold, and that threshold IS the rating: Ronin was 5-of-9 and four of those keys sat on one company's servers. Harmony was 2-of-5. We publish the signer count and the threshold wherever they exist, and where a project will not state them, that silence is scored as the risk it is.
Scored 2 of 10 against a category median of 4, which places it 16th of 16 among cross-chain bridges on this criterion. At a 40% weight that is 0.80 points below the median contribution of the weighted total. The best score in the category is 10, the worst 2.
The upgrade key: 1/10
The assumption that quietly overrides the whitepaper. A bridge whose contracts can be upgraded by a small multisig HAS that multisig as its real trust model, whatever the architecture diagram says — and Nomad proves it: the bug that lost $186m was introduced BY an upgrade. So we ask who holds upgrade authority, and we score the answer rather than the design.
Scored 1 of 10 against a category median of 3, which places it 16th of 16 among cross-chain bridges on this criterion. At a 15% weight that is 0.30 points below the median contribution of the weighted total. The best score in the category is 7, the worst 1.
Incidents — and did users get paid: 9/10
Every exploit with its root cause, and then the column nobody else publishes: were users made whole, and is that INDEPENDENTLY confirmed or merely claimed? Read the results carefully, because they do not mean what people think. Reimbursement in this category has tracked the sponsor’s balance sheet, not the bridge’s security. That makes "they paid people back last time" close to worthless as a safety signal, and we score it accordingly.
Scored 9 of 10 against a category median of 9, which places it 7th of 16 among cross-chain bridges on this criterion. At a 25% weight that is exactly level with the median of the weighted total. The best score in the category is 10, the worst 3.
Audits and transparency: 5/10
Named firms, dated reports, published. An unnamed audit is not an audit. Undisclosed validator counts are scored as undisclosed, not assumed benign.
Scored 5 of 10 against a category median of 5.5, which places it 9th of 16 among cross-chain bridges on this criterion. At a 10% weight that is 0.05 points below the median contribution of the weighted total. The best score in the category is 8, the worst 4.
Cost and speed: 8/10
Deliberately the smallest weight, and one qualification matters more than the number: we refuse to treat the canonical bridge’s seven-day withdrawal window as a defect. It is not a delay that clever engineering removed — it is the exact period during which Ethereum can be used to prove a withdrawal fraudulent. A fast bridge is fast for one reason: it substituted somebody’s signature for that proof.
Scored 8 of 10 against a category median of 6, which places it 4th of 16 among cross-chain bridges on this criterion. At a 10% weight that is 0.20 points above the median contribution of the weighted total. The best score in the category is 9, the worst 5.
Other measurements
Its nearest neighbours in this ranking
| # | Entry | Trust assumption | How it differs |
|---|---|---|---|
| 11 | LayerZero v2 / Stargate | 3 | Ahead by 1 on trust assumption. |
| 12 | Synapse | 3 | Ahead by 1 on trust assumption. |
| 14 | Socket / Bungee | 3 | Ahead by 1 on trust assumption. |
| 15 | THORChain | 3 | Ahead by 1 on trust assumption. |
Questions about this score
Is the Polygon bridge canonical like Arbitrum's?
+
No, and this is the single most important correction in our bridge rating. Arbitrum's withdrawals are proven to Ethereum through a fraud-proof system with no committee. Polygon's PoS contracts on Ethereum are controlled by a 5-of-9 multisig, per Polygon's own docs — the same threshold that lost Ronin $625 million.
Has the Polygon bridge ever been exploited?
+
No. Ronin had never been exploited either, right up until it was. A clean record on a 5-of-9 multisig tells you that five people have not yet colluded and have not yet been compromised, which is a different statement from the security a proof system provides.