How Does Axelar Work?

Bridge|Risk C-|6 mechanisms|5 interactions

Axelar is a cross-chain messaging network connecting 55+ blockchains via General Message Passing (GMP). Its security comes from a Cosmos-SDK Proof-of-Stake validator set (~75 validators) that signs threshold-BLS attestations for cross-chain messages. This is the classic 'external validator set' bridge security model — well-understood but with well-known failure modes. After the April 2026 KelpDAO LayerZero exploit ($292M) shifted cross-chain security into the spotlight, every bridge's validator-to-value ratio is under scrutiny. Axelar's Interchain Token Service (ITS) ships canonical cross-chain tokens with similar mint-authority architecture to LayerZero OFT — which means it inherits the same class of risk that just burned Kelp.

TVL

$137M

Sector

Bridge

Risk Grade

C-

Value Grade

D

Core Mechanisms

8.1.3 Message-passing bridges

Axelar General Message Passing (GMP) via external validator set

Core protocol is a Cosmos-based validator network that observes source-chain events and signs threshold-BLS attestations to be relayed to destination chains. Classic external validator bridge model.

8.1.3 Message-passing bridges

Novel

Interchain Token Service (ITS) for canonical cross-chain tokens

ITS provides canonical cross-chain token deployment primitives. Each ITS-issued token trusts the Axelar validator set for supply integrity across chains — similar to LayerZero OFT pattern exploited in Kelp.

3.1.1 Linear / pro-rata staking

AXL proof-of-stake (75+ validators, top 75 by stake)

Standard Cosmos-SDK PoS consensus. AXL delegators stake to validators who sign cross-chain messages.

3.2.1 Algorithmic slashing

Double-sign slashing + downtime slashing

Standard Cosmos slashing primitives. Does not yet slash for incorrect cross-chain message signing (key weakness).

8.4.1 Relayer fee models

Novel

Gas service paid in source-chain gas token, converted to destination fee

Axelar's Gas Service lets users pay cross-chain message fees on the source chain; service handles destination-chain gas provisioning. Nontrivial and relatively novel.

5.1.1 Token-weighted voting

AXL governance

Standard Cosmos governance via AXL holders.

How the Pieces Interact

External validator-set securityValue bridged relative to stakeCritical

If AXL market cap and staked AXL fall below 3x value bridged, it becomes economically rational for a supermajority to collude and forge messages. Post-KelpDAO, this classic bridge-economics attack is newly relevant.

GMP attestation signingDownstream application trust assumptionsHigh

Applications using GMP (e.g., Squid router, Microsoft xRPC, ITS tokens) inherit Axelar security. A single Axelar validator-set compromise cascades to every downstream app.

ITS cross-chain tokensPer-chain mint authorityHigh

Any ITS token relies on Axelar's signature validity to mint on destination chains. A forged attestation (via validator collusion OR bug) mints unbacked tokens — same architectural shape as the Kelp rsETH exploit.

No slashing for incorrect cross-chain signingValidator incentive alignmentHigh

Validators who sign an invalid cross-chain message face no on-chain slashing beyond standard double-sign slashing. Enforcement relies on governance + social pressure, not code.

Gas service liquidityCross-chain message latencyMedium

If the Gas Service runs low on destination-chain gas, messages can stall. Operational hazard rather than a loss-of-funds vector, but can halt arbitrary applications.

What Could Go Wrong

  1. Validator-set security model — attackers need to compromise a supermajority of Axelar validators to forge messages; economic cost = 2/3 of AXL staked, which is modest vs the value bridged
  2. KelpDAO April 2026 $292M LayerZero exploit demonstrates that bridge-config flaws are now the dominant DeFi exploit vector; Axelar connects 55+ chains so the per-chain configuration surface is vast
  3. General Message Passing (GMP) is a generic cross-chain RPC — any application using GMP inherits the security assumptions of the Axelar validator set

Validator Supermajority Collusion or Compromise

Tail

Trigger: An attacker achieves collusion, coercion, or key compromise over 2/3+ of Axelar validators' signing power, enabling forgery of cross-chain messages

  1. 1.Attacker compromises validator keys (supply-chain attack, insider, etc.) or organizes collusion Attacker can sign arbitrary cross-chain messages
  2. 2.Attacker forges ITS mint messages or asset-transfer messages on target chains Unbacked tokens minted on destination chain(s)
  3. 3.Attacker drains liquidity from paired pools (DEXs, lending) using counterfeit tokens Real value extracted
  4. 4.Downstream applications (Squid, etc.) accrue losses and/or halt Ecosystem-wide damage across all Axelar-dependent protocols
  5. 5.Axelar governance attempts rollback or hard fork; validators and chains coordinate recovery Extended halt of cross-chain messaging; trust damage persists

Risk Profile at a Glance

Mechanism Novelty8/15
Interaction Severity14/20
Oracle Surface6/10
Documentation Gaps6/10
Track Record10/15
Scale Exposure5/10
Regulatory Risk4/10
Vitality Risk4/10
C-

Overall: C- (57/100)

Lower score = safer

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