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Security audit

CamScanner Erase Handwriting

Security checks for vulnerabilities and agentic risk

Overview

This skill does what it says: it sends a user-selected image to CamScanner to remove handwriting and saves the processed result locally.

Install only if you are comfortable sending the selected document image to CamScanner's service. Avoid using it on highly sensitive medical, legal, financial, identity, or confidential business documents unless that third-party processing is acceptable to you.

A.I.G

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

SkillSpector

Vulnerability Patterns
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Trigger AbuseOverly Broad Trigger, Shadow Command Trigger, Keyword Baiting Trigger
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
Findings (7)

Vague Triggers

Medium
Category
Not specified by scanner
Confidence
94% confidence
Finding

The description starts with several specific trigger phrases, but then broadens activation to 'when the user has an image with handwritten content that needs to be removed.' That condition is ambiguous and lacks clear boundaries or exclusions, which could cause unintended invocation in ordinary image-editing contexts.

Content

No source excerpt is available for this finding.

External Transmission

Medium
Category
Data Exfiltration
Confidence
97% confidence
Finding

This command uploads a local image file to a third-party server, which is an external data transmission of potentially sensitive document contents. Even though the skill discloses the behavior, sending user files off-platform creates confidentiality and privacy risk if the document contains personal, financial, medical, or legal information.

Content

Scanner excerpt · SKILL.md (reported line 50)May include surrounding context.

bash
BASE="https://ai-tools.camscanner.com"

IN_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/upload_file/execute" \
  -H "Content-Type: application/octet-stream" \
  --data-binary "@/path/to/image.jpg" | jq -r '.tool_result.data.file_id')

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 74)May include surrounding context.

Step 2: Enhance Image (Erase Handwriting)

bash
OUT_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/enhance_image/execute" \
  -H "Content-Type: application/json" \
  -d "{\"file_id\":\"$IN_FILE_ID\",\"enhance_mode\":9,\"output_mode\":\"file_id\"}" \
  | jq -r '.tool_result.data.file_id')

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 133)May include surrounding context.

Step 2: Enhance Image (Erase Handwriting)

bash
OUT_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/enhance_image/execute" \
  -H "Content-Type: application/json" \
  -d "{\"file_id\":\"$IN_FILE_ID\",\"enhance_mode\":9,\"output_mode\":\"file_id\"}" \
  | jq -r '.tool_result.data.file_id')

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 158)May include surrounding context.

Step 2: Enhance Image (Erase Handwriting)

bash
OUT_FILE_ID=$(curl -sS -X POST "$BASE/v1/tools/enhance_image/execute" \
  -H "Content-Type: application/json" \
  -d "{\"file_id\":\"$IN_FILE_ID\",\"enhance_mode\":9,\"output_mode\":\"file_id\"}" \
  | jq -r '.tool_result.data.file_id')

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 99)May include surrounding context.

Step 3: Download Result

bash
curl -sS -X POST "$BASE/v1/tools/download_file/execute?response_mode=raw" \
  -H "Content-Type: application/json" \
  -d "{\"file_id\":\"$OUT_FILE_ID\"}" \
  -o /path/to/output.jpg

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 139)May include surrounding context.

md
| jq -r '.tool_result.data.file_id')

# Download
curl -sS -X POST "$BASE/v1/tools/download_file/execute?response_mode=raw" \
  -H "Content-Type: application/json" \
  -d "{\"file_id\":\"$OUT_FILE_ID\"}" \
  -o "$OUTPUT_FILE"

Static analysis

No suspicious patterns detected.