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Security audit

Qrcoin

Security checks for vulnerabilities and agentic risk

Overview

The skill is coherent for QR Coin auction use, but it guides users through USDC approvals and blockchain transactions without enough safety scoping for real financial risk.

Review this skill carefully before installing. It is for real USDC transactions on Base, so users should verify the contract address, network, function, URL, and amount in Bankr or their wallet, approve only the minimum needed, and revoke unused allowances after bidding.

Vulnerability Patterns
  • Skill Instruction HijackingAlters the agent's session goals or safety constraints when the skill loads
  • Agent Memory PoisoningWrites attacker-controlled rules into memory that affect later sessions
  • Remote Payload Retrieval and ExecutionFetches external code whose behavior can change after review
  • Embedded Malicious CodeShips malicious scripts inside the skill and executes them locally
  • Unauthorized Access and Privilege EscalationObtains permissions beyond the task's legitimate needs
Vulnerability Patterns
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
Findings (5)

External Transmission

Medium
Category
Data Exfiltration
Content
Always query this first to get the active auction ID before bidding.

```bash
curl -s -X POST https://mainnet.base.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x7309779122069EFa06ef71a45AE0DB55A259A176","data":"0x7d9f6db5"},"latest"],"id":1}' \
  | jq -r '.result' | xargs printf "%d\n"
Confidence
60% confidence
Finding
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

External Transmission

Medium
Category
Data Exfiltration
Content
Always query this first to get the active auction ID before bidding.

```bash
curl -s -X POST https://mainnet.base.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x7309779122069EFa06ef71a45AE0DB55A259A176","data":"0x7d9f6db5"},"latest"],"id":1}' \
  | jq -r '.result' | xargs printf "%d\n"
Confidence
60% confidence
Finding
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

External Transmission

Medium
Category
Data Exfiltration
Content
Always query this first to get the active auction ID before bidding.

```bash
curl -s -X POST https://mainnet.base.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x7309779122069EFa06ef71a45AE0DB55A259A176","data":"0x7d9f6db5"},"latest"],"id":1}' \
  | jq -r '.result' | xargs printf "%d\n"
Confidence
60% confidence
Finding
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

External Transmission

Medium
Category
Data Exfiltration
Content
Always query this first to get the active auction ID before bidding.

```bash
curl -s -X POST https://mainnet.base.org \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x7309779122069EFa06ef71a45AE0DB55A259A176","data":"0x7d9f6db5"},"latest"],"id":1}' \
  | jq -r '.result' | xargs printf "%d\n"
Confidence
60% confidence
Finding
Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Missing User Warnings

Medium
Confidence
97% confidence
Finding
The skill instructs users to approve USDC and submit on-chain transactions without prominently warning that approvals can grant spending power and that blockchain transactions are generally irreversible once signed. In this context, the omission is security-relevant because users are being guided to move funds and set allowances to a contract, creating real financial risk if the contract, amount, or network is wrong or later abused.

Static analysis

No suspicious patterns detected.