fix: improve input validation, error handling, and path safety

cli/azd/.vscode/cspell.yaml

@@ -255,6 +255,12 @@ overrides:
   - filename: pkg/project/service_target_dotnet_containerapp.go
     words:
       - IMAGENAME
+  - filename: internal/vsrpc/server.go
+    words:
+      - CSWSH
+  - filename: pkg/extensions/manager.go
+    words:
+      - myext
   - filename: extensions/microsoft.azd.extensions/internal/resources/languages/**/.gitignore
     words:
       - rsuser

cli/azd/cmd/vs_server.go

@@ -101,7 +101,8 @@ func (s *vsServerAction) Run(ctx context.Context) (*actions.ActionResult, error)
 		}
 
 		listener = tls.NewListener(listener, config)
-		res.CertificateBytes = new(base64.StdEncoding.EncodeToString(derBytes))
+		certBytesStr := base64.StdEncoding.EncodeToString(derBytes)
+		res.CertificateBytes = &certBytesStr
 	}
 
 	resString, err := json.Marshal(res)

cli/azd/extensions/azure.ai.agents/internal/cmd/init.go

@@ -767,7 +767,10 @@ func (a *InitAction) parseAndSetProjectResourceId(ctx context.Context) error {
 	}
 
 	// Create FoundryProjectsClient and get connections
-	foundryClient := azure.NewFoundryProjectsClient(foundryProject.AiAccountName, foundryProject.AiProjectName, a.credential)
+	foundryClient, err := azure.NewFoundryProjectsClient(foundryProject.AiAccountName, foundryProject.AiProjectName, a.credential)
+	if err != nil {
+		return fmt.Errorf("creating Foundry client: %w", err)
+	}
 	connections, err := foundryClient.GetAllConnections(ctx)
 	if err != nil {
 		fmt.Printf("Could not get Microsoft Foundry project connections to initialize AZURE_CONTAINER_REGISTRY_ENDPOINT: %v. Please set this environment variable manually.\n", err)

cli/azd/extensions/azure.ai.agents/internal/cmd/init_from_code.go

@@ -1351,7 +1351,10 @@ func (a *InitFromCodeAction) processExistingFoundryProject(ctx context.Context,
 	}
 
 	// Create FoundryProjectsClient and get connections
-	foundryClient := azure.NewFoundryProjectsClient(foundryProject.AccountName, foundryProject.ProjectName, a.credential)
+	foundryClient, err := azure.NewFoundryProjectsClient(foundryProject.AccountName, foundryProject.ProjectName, a.credential)
+	if err != nil {
+		return fmt.Errorf("creating Foundry client: %w", err)
+	}
 	connections, err := foundryClient.GetAllConnections(ctx)
 	if err != nil {
 		fmt.Printf("Could not get Microsoft Foundry project connections to initialize AZURE_CONTAINER_REGISTRY_ENDPOINT: %v. Please set this environment variable manually.\n", err)

cli/azd/extensions/azure.ai.agents/internal/pkg/azure/foundry_projects_client.go

@@ -10,6 +10,8 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
+	"strings"
 
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore"
 	"github.com/Azure/azure-sdk-for-go/sdk/azcore/policy"
@@ -19,13 +21,25 @@ import (
 
 // FoundryProjectsClient provides methods to interact with Microsoft Foundry projects
 type FoundryProjectsClient struct {
-	baseEndpoint string
-	apiVersion   string
-	pipeline     runtime.Pipeline
+	baseEndpoint  string
+	baseOriginURL *url.URL // cached parsed base URL for SSRF origin checks
+	apiVersion    string
+	pipeline      runtime.Pipeline
 }
 
 // NewFoundryProjectsClient creates a new instance of FoundryProjectsClient
-func NewFoundryProjectsClient(accountName string, projectName string, cred azcore.TokenCredential) *FoundryProjectsClient {
+func NewFoundryProjectsClient(
+	accountName string,
+	projectName string,
+	cred azcore.TokenCredential,
+) (*FoundryProjectsClient, error) {
+	if strings.TrimSpace(accountName) == "" {
+		return nil, fmt.Errorf("accountName must not be empty")
+	}
+	if strings.TrimSpace(projectName) == "" {
+		return nil, fmt.Errorf("projectName must not be empty")
+	}
+
 	baseEndpoint := fmt.Sprintf("https://%s.services.ai.azure.com/api/projects/%s", accountName, projectName)
 
 	userAgent := fmt.Sprintf("azd-ext-azure-ai-agents/%s", version.Version)
@@ -48,11 +62,17 @@ func NewFoundryProjectsClient(accountName string, projectName string, cred azcor
 		clientOptions,
 	)
 
-	return &FoundryProjectsClient{
-		baseEndpoint: baseEndpoint,
-		apiVersion:   "2025-11-15-preview",
-		pipeline:     pipeline,
+	parsedBase, err := url.Parse(baseEndpoint)
+	if err != nil {
+		return nil, fmt.Errorf("invalid base endpoint URL: %w", err)
 	}
+
+	return &FoundryProjectsClient{
+		baseEndpoint:  baseEndpoint,
+		baseOriginURL: parsedBase,
+		apiVersion:    "2025-11-15-preview",
+		pipeline:      pipeline,
+	}, nil
 }
 
 // Connection-related types
@@ -144,7 +164,8 @@ func (c *FoundryProjectsClient) GetPagedConnections(ctx context.Context) (*Paged
 // GetConnectionWithCredentials retrieves a specific connection with its credentials
 func (c *FoundryProjectsClient) GetConnectionWithCredentials(ctx context.Context, name string) (*Connection, error) {
 	targetEndpoint := fmt.Sprintf(
-		"%s/connections/%s/getConnectionWithCredentials?api-version=%s", c.baseEndpoint, name, c.apiVersion)
+		"%s/connections/%s/getConnectionWithCredentials?api-version=%s",
+		c.baseEndpoint, url.PathEscape(name), c.apiVersion)
 
 	req, err := runtime.NewRequest(ctx, http.MethodPost, targetEndpoint)
 	if err != nil {
@@ -191,6 +212,9 @@ func (c *FoundryProjectsClient) GetAllConnections(ctx context.Context) ([]Connec
 
 	// Continue fetching pages while there's a next link
 	for nextLink != nil && *nextLink != "" {
+		if err := c.validateNextLinkOrigin(*nextLink); err != nil {
+			return nil, fmt.Errorf("refusing to follow pagination link: %w", err)
+		}
 		pagedConnections, err := c.getNextPage(ctx, *nextLink)
 		if err != nil {
 			return nil, err
@@ -204,6 +228,36 @@ func (c *FoundryProjectsClient) GetAllConnections(ctx context.Context) ([]Connec
 	return allConnections, nil
 }
 
+// validateNextLinkOrigin ensures that a pagination nextLink URL points to the same
+// origin (scheme + host) as the client's base endpoint. This prevents SSRF attacks
+// where a malicious API response redirects pagination to an attacker-controlled server.
+func (c *FoundryProjectsClient) validateNextLinkOrigin(nextLink string) error {
+	if c.baseOriginURL == nil {
+		return fmt.Errorf("base endpoint URL not initialized")
+	}
+
+	linkURL, err := url.Parse(nextLink)
+	if err != nil {
+		return fmt.Errorf("invalid nextLink URL: %w", err)
+	}
+
+	// Reject scheme-relative URLs (e.g., "//evil.com/path") and URLs without an explicit scheme.
+	// These could bypass origin checks or behave unpredictably.
+	if linkURL.Scheme == "" {
+		return fmt.Errorf("nextLink must have an explicit scheme, got %q", nextLink)
+	}
+
+	if !strings.EqualFold(linkURL.Scheme, c.baseOriginURL.Scheme) ||
+		!strings.EqualFold(linkURL.Host, c.baseOriginURL.Host) {
+		return fmt.Errorf(
+			"nextLink origin mismatch: expected %s://%s, got %s://%s",
+			c.baseOriginURL.Scheme, c.baseOriginURL.Host, linkURL.Scheme, linkURL.Host,
+		)
+	}
+
+	return nil
+}
+
 // getNextPage fetches a single page of connections from the given URL
 func (c *FoundryProjectsClient) getNextPage(ctx context.Context, url string) (*PagedConnection, error) {
 	req, err := runtime.NewRequest(ctx, http.MethodGet, url)