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Security audit

OAuth

Security checks for vulnerabilities and agentic risk

Overview

This is a small OAuth/OIDC guidance skill with no executable code, hidden behavior, or unusual permissions.

This skill appears safe to install as reference guidance for OAuth/OIDC work. Treat it as a concise checklist, and still verify implementation details against the specific identity provider and current standards when building production authentication flows.

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
  • Privilege EscalationExcessive Permissions, Sudo/Root Execution, Credential Access
  • Prompt InjectionInstruction Override, Hidden Instructions, Exfiltration Commands
  • Data ExfiltrationExternal Transmission, Env Variable Harvesting, File System Enumeration
  • Supply ChainUnpinned Dependencies, External Script Fetching, Obfuscated Code
  • Excessive AgencyUnrestricted Tool Access, Autonomous Decision Making, Scope Creep
Findings (5)

Credential Access

High
Category
Privilege Escalation
Content
## Tokens

- Access token: short-lived (minutes to hour), used for API access
- Refresh token: longer-lived, used only at token endpoint for new access tokens
- ID token (OIDC): JWT with user identity claims—don't use for API authorization
- Don't send refresh tokens to resource servers—only to authorization server
Confidence
70% confidence
Finding
Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Credential Access

High
Category
Privilege Escalation
Content
## Tokens

- Access token: short-lived (minutes to hour), used for API access
- Refresh token: longer-lived, used only at token endpoint for new access tokens
- ID token (OIDC): JWT with user identity claims—don't use for API authorization
- Don't send refresh tokens to resource servers—only to authorization server
Confidence
70% confidence
Finding
Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Credential Access

High
Category
Privilege Escalation
Content
## Tokens

- Access token: short-lived (minutes to hour), used for API access
- Refresh token: longer-lived, used only at token endpoint for new access tokens
- ID token (OIDC): JWT with user identity claims—don't use for API authorization
- Don't send refresh tokens to resource servers—only to authorization server
Confidence
70% confidence
Finding
Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Credential Access

High
Category
Privilege Escalation
Content
## Common Mistakes

- Using access token as identity proof—use ID token for authentication
- Storing tokens in localStorage—vulnerable to XSS; prefer httpOnly cookies or memory
- Not validating redirect_uri—allows open redirect attacks
- Accepting tokens from URL fragment in backend—fragment never reaches server
Confidence
70% confidence
Finding
Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Credential Access

High
Category
Privilege Escalation
Content
## Common Mistakes

- Using access token as identity proof—use ID token for authentication
- Storing tokens in localStorage—vulnerable to XSS; prefer httpOnly cookies or memory
- Not validating redirect_uri—allows open redirect attacks
- Accepting tokens from URL fragment in backend—fragment never reaches server
Confidence
70% confidence
Finding
Code accesses credential files (SSH keys, AWS credentials, etc.). This could indicate credential theft attempts.

Static analysis

No suspicious patterns detected.