diff --git a/src/install/PackageManager/security_scanner.zig b/src/install/PackageManager/security_scanner.zig
index fd702c3373..d9a9acb580 100644
--- a/src/install/PackageManager/security_scanner.zig
+++ b/src/install/PackageManager/security_scanner.zig
@@ -383,6 +383,7 @@ const PackageCollector = struct {
         const root_pkg_id: PackageID = 0;
         const root_deps = pkg_dependencies[root_pkg_id];
 
+        // collect all npm deps from the root package
         for (root_deps.begin()..root_deps.end()) |_dep_id| {
             const dep_id: DependencyID = @intCast(_dep_id);
             const dep_pkg_id = this.manager.lockfile.buffers.resolutions.items[dep_id];
@@ -408,6 +409,39 @@ const PackageCollector = struct {
                 .dep_path = dep_path_buf,
             });
         }
+
+        // and collect npm deps from workspace packages
+        for (0..pkgs.len) |pkg_idx| {
+            const pkg_id: PackageID = @intCast(pkg_idx);
+            if (pkg_resolutions[pkg_id].tag != .workspace) continue;
+
+            const workspace_deps = pkg_dependencies[pkg_id];
+            for (workspace_deps.begin()..workspace_deps.end()) |_dep_id| {
+                const dep_id: DependencyID = @intCast(_dep_id);
+                const dep_pkg_id = this.manager.lockfile.buffers.resolutions.items[dep_id];
+
+                if (dep_pkg_id == invalid_package_id) continue;
+
+                const dep_res = pkg_resolutions[dep_pkg_id];
+                if (dep_res.tag != .npm) continue;
+
+                if ((try this.dedupe.getOrPut(dep_pkg_id)).found_existing) continue;
+
+                var pkg_path_buf = std.array_list.Managed(PackageID).init(this.manager.allocator);
+                try pkg_path_buf.append(pkg_id);
+                try pkg_path_buf.append(dep_pkg_id);
+
+                var dep_path_buf = std.array_list.Managed(DependencyID).init(this.manager.allocator);
+                try dep_path_buf.append(dep_id);
+
+                try this.queue.writeItem(.{
+                    .pkg_id = dep_pkg_id,
+                    .dep_id = dep_id,
+                    .pkg_path = pkg_path_buf,
+                    .dep_path = dep_path_buf,
+                });
+            }
+        }
     }
 
     pub fn collectUpdatePackages(this: *PackageCollector) !void {
@@ -427,7 +461,7 @@ const PackageCollector = struct {
                 for (0..pkgs.len) |_pkg_id| update_dep_id: {
                     const pkg_id: PackageID = @intCast(_pkg_id);
                     const pkg_res = pkg_resolutions[pkg_id];
-                    if (pkg_res.tag != .root) continue;
+                    if (pkg_res.tag != .root and pkg_res.tag != .workspace) continue;
 
                     const pkg_deps = pkg_dependencies[pkg_id];
                     for (pkg_deps.begin()..pkg_deps.end()) |_dep_id| {
diff --git a/test/cli/install/bun-security-scanner-workspaces.test.ts b/test/cli/install/bun-security-scanner-workspaces.test.ts
new file mode 100644
index 0000000000..c9e02b92d6
--- /dev/null
+++ b/test/cli/install/bun-security-scanner-workspaces.test.ts
@@ -0,0 +1,276 @@
+import { bunEnv, bunExe, tempDirWithFiles } from "harness";
+import { join } from "node:path";
+import { getRegistry, startRegistry, stopRegistry } from "./simple-dummy-registry";
+
+test("security scanner receives packages from workspace dependencies", async () => {
+  const registryUrl = await startRegistry(false);
+
+  try {
+    const registry = getRegistry();
+    if (!registry) {
+      throw new Error("Registry not found");
+    }
+
+    registry.clearRequestLog();
+    registry.setScannerBehavior("none");
+
+    // Create a workspace setup with root package and multiple workspace packages
+    const files = {
+      "package.json": JSON.stringify(
+        {
+          name: "workspace-root",
+          private: true,
+          workspaces: ["packages/*"],
+        },
+        null,
+        2,
+      ),
+      "packages/app1/package.json": JSON.stringify(
+        {
+          name: "app1",
+          dependencies: {
+            "left-pad": "1.3.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "packages/app2/package.json": JSON.stringify(
+        {
+          name: "app2",
+          dependencies: {
+            "is-even": "1.0.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "packages/lib1/package.json": JSON.stringify(
+        {
+          name: "lib1",
+          dependencies: {
+            "is-odd": "1.0.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "scanner.js": `export const scanner = {
+  version: "1",
+  scan: async function(payload) {
+    console.error("SCANNER_RAN: " + payload.packages.length + " packages");
+    return [];
+  }
+}`,
+    };
+
+    const dir = tempDirWithFiles("scanner-workspaces", files);
+
+    await Bun.write(
+      join(dir, "bunfig.toml"),
+      `[install]
+cache.disable = true
+registry = "${registryUrl}/"
+
+[install.security]
+scanner = "./scanner.js"`,
+    );
+
+    const { stdout, stderr } = Bun.spawn({
+      cmd: [bunExe(), "install"],
+      cwd: dir,
+      stdout: "pipe",
+      stderr: "pipe",
+      env: bunEnv,
+    });
+
+    const output = (await stdout.text()) + (await stderr.text());
+
+    // The scanner should receive packages from all workspace dependencies
+    expect(output).toContain("SCANNER_RAN:");
+
+    // Extract the number of packages from the output
+    const match = output.match(/SCANNER_RAN: (\d+) packages/);
+    expect(match).toBeTruthy();
+
+    const packagesScanned = parseInt(match![1], 10);
+    // Exact package count: left-pad, is-even, is-odd (is-even <-> is-odd have circular deps)
+    expect(packagesScanned).toBe(3);
+  } finally {
+    stopRegistry();
+  }
+});
+
+test("security scanner receives packages from workspace dependencies with hoisted linker", async () => {
+  const registryUrl = await startRegistry(false);
+
+  try {
+    const registry = getRegistry();
+    if (!registry) {
+      throw new Error("Registry not found");
+    }
+
+    registry.clearRequestLog();
+    registry.setScannerBehavior("none");
+
+    const files = {
+      "package.json": JSON.stringify(
+        {
+          name: "workspace-root",
+          private: true,
+          workspaces: ["packages/*"],
+        },
+        null,
+        2,
+      ),
+      "packages/app1/package.json": JSON.stringify(
+        {
+          name: "app1",
+          dependencies: {
+            "left-pad": "1.3.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "packages/app2/package.json": JSON.stringify(
+        {
+          name: "app2",
+          dependencies: {
+            "is-even": "1.0.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "scanner.js": `export const scanner = {
+  version: "1",
+  scan: async function(payload) {
+    console.error("SCANNER_RAN: " + payload.packages.length + " packages");
+    return [];
+  }
+}`,
+    };
+
+    const dir = tempDirWithFiles("scanner-workspaces-hoisted", files);
+
+    await Bun.write(
+      join(dir, "bunfig.toml"),
+      `[install]
+cache.disable = true
+linker = "hoisted"
+registry = "${registryUrl}/"
+
+[install.security]
+scanner = "./scanner.js"`,
+    );
+
+    const { stdout, stderr } = Bun.spawn({
+      cmd: [bunExe(), "install"],
+      cwd: dir,
+      stdout: "pipe",
+      stderr: "pipe",
+      env: bunEnv,
+    });
+
+    const output = (await stdout.text()) + (await stderr.text());
+
+    expect(output).toContain("SCANNER_RAN:");
+
+    const match = output.match(/SCANNER_RAN: (\d+) packages/);
+    expect(match).toBeTruthy();
+
+    const packagesScanned = parseInt(match![1], 10);
+    // Exact package count: left-pad, is-even, is-odd (is-even <-> is-odd have circular deps)
+    expect(packagesScanned).toBe(3);
+  } finally {
+    stopRegistry();
+  }
+});
+
+test("security scanner receives packages from workspace dependencies with isolated linker", async () => {
+  const registryUrl = await startRegistry(false);
+
+  try {
+    const registry = getRegistry();
+    if (!registry) {
+      throw new Error("Registry not found");
+    }
+
+    registry.clearRequestLog();
+    registry.setScannerBehavior("none");
+
+    const files = {
+      "package.json": JSON.stringify(
+        {
+          name: "workspace-root",
+          private: true,
+          workspaces: ["packages/*"],
+        },
+        null,
+        2,
+      ),
+      "packages/app1/package.json": JSON.stringify(
+        {
+          name: "app1",
+          dependencies: {
+            "left-pad": "1.3.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "packages/app2/package.json": JSON.stringify(
+        {
+          name: "app2",
+          dependencies: {
+            "is-even": "1.0.0",
+          },
+        },
+        null,
+        2,
+      ),
+      "scanner.js": `export const scanner = {
+  version: "1",
+  scan: async function(payload) {
+    console.error("SCANNER_RAN: " + payload.packages.length + " packages");
+    return [];
+  }
+}`,
+    };
+
+    const dir = tempDirWithFiles("scanner-workspaces-isolated", files);
+
+    await Bun.write(
+      join(dir, "bunfig.toml"),
+      `[install]
+cache.disable = true
+linker = "isolated"
+registry = "${registryUrl}/"
+
+[install.security]
+scanner = "./scanner.js"`,
+    );
+
+    const { stdout, stderr } = Bun.spawn({
+      cmd: [bunExe(), "install"],
+      cwd: dir,
+      stdout: "pipe",
+      stderr: "pipe",
+      env: bunEnv,
+    });
+
+    const output = (await stdout.text()) + (await stderr.text());
+
+    expect(output).toContain("SCANNER_RAN:");
+
+    const match = output.match(/SCANNER_RAN: (\d+) packages/);
+    expect(match).toBeTruthy();
+
+    const packagesScanned = parseInt(match![1], 10);
+    // Exact package count: left-pad, is-even, is-odd (is-even <-> is-odd have circular deps)
+    expect(packagesScanned).toBe(3);
+  } finally {
+    stopRegistry();
+  }
+});