springboot-security

Spring Boot Security Review

Use when adding auth, handling input, creating endpoints, or dealing with secrets.

When to Activate

• Adding authentication (JWT, OAuth2, session-based)
• Implementing authorization (@PreAuthorize, role-based access)
• Validating user input (Bean Validation, custom validators)
• Configuring CORS, CSRF, or security headers
• Managing secrets (Vault, environment variables)
• Adding rate limiting or brute-force protection
• Scanning dependencies for CVEs

Authentication

• Prefer stateless JWT or opaque tokens with revocation list
• Use httpOnly, Secure, SameSite=Strict cookies for sessions
• Validate tokens with OncePerRequestFilter or resource server

@Component
public class JwtAuthFilter extends OncePerRequestFilter {
  private final JwtService jwtService;

  public JwtAuthFilter(JwtService jwtService) {
    this.jwtService = jwtService;
  }

  @Override
  protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response,
      FilterChain chain) throws ServletException, IOException {
    String header = request.getHeader(HttpHeaders.AUTHORIZATION);
    if (header != null && header.startsWith("Bearer ")) {
      String token = header.substring(7);
      Authentication auth = jwtService.authenticate(token);
      SecurityContextHolder.getContext().setAuthentication(auth);
    }
    chain.doFilter(request, response);
  }
}

Authorization

• Enable method security: @EnableMethodSecurity
• Use @PreAuthorize("hasRole('ADMIN')") or @PreAuthorize("@authz.canEdit(#id)")
• Deny by default; expose only required scopes

@RestController
@RequestMapping("/api/admin")
public class AdminController {

  @PreAuthorize("hasRole('ADMIN')")
  @GetMapping("/users")
  public List<UserDto> listUsers() {
    return userService.findAll();
  }

  @PreAuthorize("@authz.isOwner(#id, authentication)")
  @DeleteMapping("/users/{id}")
  public ResponseEntity<Void> deleteUser(@PathVariable Long id) {
    userService.delete(id);
    return ResponseEntity.noContent().build();
  }
}