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Security audit

eBay Product Data API - Live Listings, Units Sold, Sellers

Security checks for vulnerabilities and agentic risk

Overview

This skill provides eBay research through a disclosed third-party API, with expected authentication and credit costs.

Use a Scavio-specific key stored in your environment or secret store. Scavio receives your searches and requested listing or seller identifiers, and requests consume credits. This review covers the supplied instructions, not the provider's internal data handling or live API behavior.

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
  • MCP Tool PoisoningHidden Instructions, Unicode Deception, Parameter Description Injection
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
Findings (6)

Description-Behavior Mismatch

High
Category
MCP Tool Poisoning
Confidence
97% confidence
Finding

Setting an API-key environment variable could support the declared service, but the supplied chunk contains no implementation or invocation of its advertised capabilities. The mismatch is missing declared functionality, not an undeclared or malicious action. Additional code could change this assessment.

Content

No source excerpt is available for this finding.

External Transmission

Medium
Category
Data Exfiltration
Confidence
70% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 128)May include surrounding context.

md
HEADERS = {"Authorization": f"Bearer {API_KEY}"}

# 1. Price research: used asks, with demand signals on every row
used = requests.post(f"{BASE}/api/v1/ebay/search", headers=HEADERS,
    json={"query": "nintendo switch oled", "condition": "used"}).json()
for row in used["data"]["products"]:
    print(row["price"], row["sold_count"], row["watchers"], row["bids"], row["url"])

External Transmission

Medium
Category
Data Exfiltration
Confidence
70% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 134)May include surrounding context.

md
print(row["price"], row["sold_count"], row["watchers"], row["bids"], row["url"])

# 2. Live listings, cheapest first, 120 per page
live = requests.post(f"{BASE}/api/v1/ebay/search", headers=HEADERS,
    json={"query": "nintendo switch oled", "sort_by": "price_low", "per_page": 120}).json()

# 3. One listing in full

External Transmission

Medium
Category
Data Exfiltration
Confidence
70% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 142)May include surrounding context.

md
json={"item_id": "168591664725"}).json()

# 4. A seller's whole catalogue: /search with seller and no query
catalogue = requests.post(f"{BASE}/api/v1/ebay/search", headers=HEADERS,
    json={"seller": "red-rock-uk", "page": 1}).json()

# 5. That seller's reputation card

External Transmission

Medium
Category
Data Exfiltration
Confidence
70% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 138)May include surrounding context.

md
json={"query": "nintendo switch oled", "sort_by": "price_low", "per_page": 120}).json()

# 3. One listing in full
item = requests.post(f"{BASE}/api/v1/ebay/product", headers=HEADERS,
    json={"item_id": "168591664725"}).json()

# 4. A seller's whole catalogue: /search with seller and no query

External Transmission

Medium
Category
Data Exfiltration
Confidence
70% confidence
Finding

Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.

Content

Scanner excerpt · SKILL.md (reported line 146)May include surrounding context.

json={"seller": "red-rock-uk", "page": 1}).json()

5. That seller's reputation card

profile = requests.post(f"{BASE}/api/v1/ebay/seller", headers=HEADERS, json={"seller": "red-rock-uk"}).json()

text