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Security audit

Poyo Nano Banana Pro

Security checks for vulnerabilities and agentic risk

Overview

This skill is a straightforward PoYo image-generation helper that discloses its external API use and API-key requirement.

Install only if you intend to use PoYo's hosted Nano Banana Pro API. Treat POYO_API_KEY as a secret, review payloads before submission, and avoid including private prompts, private image URLs, callback URLs, or other sensitive data unless you are comfortable sending them to PoYo.

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
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • MCP Least PrivilegeUnderdeclared Capability, Wildcard Permission, Missing Permission Declaration
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
Findings (11)

Credential Access

High
Category
Privilege Escalation
Confidence
70% confidence
Finding

Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Content

Scanner excerpt · references/api.md (reported line 20)May include surrounding context.

Content-Type: application/json

text

Get API keys from <https://poyo.ai/dashboard/api-key>.

Recommended skill env var:

Undeclared Tool Scope

Medium
Category
MCP Least Privilege
Confidence
82% confidence
Finding

The skill indicates shell-capable execution via its referenced script and required curl binary, but it does not declare any explicit tool scope such as permissions or allowed-tools. That creates an avoidable least-privilege gap: an agent may invoke shell functionality more broadly than intended, increasing the chance of unintended command execution or unsafe handling of secrets like POYO_API_KEY.

Content

No source excerpt is available for this finding.

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · references/api.md (reported line 54)May include surrounding context.

Generate Example

bash
curl --fail-with-body --request POST \
  --url "https://api.poyo.ai/api/generate/submit" \
  --header "Authorization: Bearer YOUR_API_KEY" \
  --header "Content-Type: application/json" \

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 3)May include surrounding context.

md
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · references/api.md (reported line 5)May include surrounding context.

md
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · references/api.md (reported line 6)May include surrounding context.

md
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · references/api.md (reported line 55)May include surrounding context.

md
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · references/api.md (reported line 77)May include surrounding context.

md
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

External Transmission

Medium
Category
Data Exfiltration
Confidence
60% 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 · scripts/submit_nano_banana_pro.sh (reported line 18)May include surrounding context.

sh
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

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 · scripts/submit_nano_banana_pro.sh (reported line 18)May include surrounding context.

sh
: "${POYO_API_KEY:?POYO_API_KEY is required}"
payload_file="$1"

curl -sS https://api.poyo.ai/api/generate/submit \
  -H "Authorization: Bearer ${POYO_API_KEY}" \
  -H 'Content-Type: application/json' \
  --data @"${payload_file}"

Missing User Warnings

Medium
Category
Not specified by scanner
Confidence
92% confidence
Finding

The script performs an HTTP request that transmits the full contents of the supplied payload file, potentially including sensitive user data, to an external service. While the command name suggests submission, there is no explicit warning, confirmation, or user-facing disclosure in the script about sending file contents off-host.

Content

No source excerpt is available for this finding.

Static analysis

No suspicious patterns detected.