diff --git a/.github/workflows/caipe-ui-tests.yml b/.github/workflows/caipe-ui-tests.yml
index 203140433b..2afc5d91cc 100644
--- a/.github/workflows/caipe-ui-tests.yml
+++ b/.github/workflows/caipe-ui-tests.yml
@@ -1,10 +1,11 @@
 name: "[CI] CAIPE UI Tests"
-description: "Run CAIPE UI Jest tests and mocked RBAC Playwright regression on pull requests"
+# description: "Run CAIPE UI Jest tests and mocked RBAC Playwright regression on pull requests"
 
 on:
   pull_request:
     paths:
       - 'ui/**'
+      - 'scripts/npm/**'
       - '!ui/README.md'
       - '!ui/**/*.md'
   push:
@@ -12,6 +13,7 @@ on:
       - main
     paths:
       - 'ui/**'
+      - 'scripts/npm/**'
       - '!ui/README.md'
       - '!ui/**/*.md'
   workflow_dispatch:
@@ -50,6 +52,10 @@ jobs:
         working-directory: ui
         run: npm ci
 
+      - name: Test npm security backports
+        working-directory: ui
+        run: node --test ../scripts/npm/*.test.mjs
+
       - name: Test External App examples
         working-directory: ui
         run: npm run test:external-app-examples
diff --git a/.github/workflows/ci-caipe-ui.yml b/.github/workflows/ci-caipe-ui.yml
index a2f56e4c11..df56b3e57e 100644
--- a/.github/workflows/ci-caipe-ui.yml
+++ b/.github/workflows/ci-caipe-ui.yml
@@ -1,5 +1,5 @@
 name: "[CI] CAIPE UI Build and Push"
-description: "Build and push CAIPE UI Docker image"
+# description: "Build and push CAIPE UI Docker image"
 
 on:
   push:
@@ -11,6 +11,7 @@ on:
     paths:
       - 'ui/**'
       - 'build/Dockerfile.caipe-ui'
+      - 'scripts/npm/**'
   workflow_dispatch:
     inputs:
       tag_version:
@@ -58,6 +59,7 @@ jobs:
             ui:
               - 'ui/**'
               - 'build/Dockerfile.caipe-ui'
+              - 'scripts/npm/**'
 
       - name: Set Outputs
         id: set-outputs
diff --git a/.github/workflows/docs-build-check.yml b/.github/workflows/docs-build-check.yml
index 4e1735753c..a6a1ee1fe6 100644
--- a/.github/workflows/docs-build-check.yml
+++ b/.github/workflows/docs-build-check.yml
@@ -5,6 +5,7 @@ on:
   pull_request:
     paths:
       - "docs/**"
+      - "scripts/npm/**"
 
 permissions:
   contents: read
@@ -41,6 +42,9 @@ jobs:
         run: |
           cd docs
           npm install
+      - name: Test npm security backports
+        working-directory: docs
+        run: node --test ../scripts/npm/*.test.mjs
       - name: Build Docusaurus site
         env:
           NODE_OPTIONS: "--max-old-space-size=8192"
diff --git a/.github/workflows/prebuild-caipe-ui.yml b/.github/workflows/prebuild-caipe-ui.yml
index 65b2789f16..60e5b4bd6e 100644
--- a/.github/workflows/prebuild-caipe-ui.yml
+++ b/.github/workflows/prebuild-caipe-ui.yml
@@ -1,5 +1,5 @@
 name: "[Prebuild] CAIPE UI Docker Build and Push"
-description: "Build and push CAIPE UI Docker image for prebuild branches"
+# description: "Build and push CAIPE UI Docker image for prebuild branches"
 
 on:
   pull_request:
@@ -10,6 +10,7 @@ on:
       - '.github/actions/publish-prebuild-manifest/**'
       - 'ui/**'
       - 'build/Dockerfile.caipe-ui'
+      - 'scripts/npm/**'
   workflow_call:
     inputs:
       pr_number:
@@ -79,6 +80,7 @@ jobs:
               .github/actions/prebuild-status \
               .github/actions/publish-prebuild-manifest \
               ui \
+              scripts/npm \
               build/Dockerfile.caipe-ui | grep -q .; then
             echo "should_build=true" >> "$GITHUB_OUTPUT"
           else
diff --git a/.github/workflows/prebuild-manual.yml b/.github/workflows/prebuild-manual.yml
index 2d99fb4e13..7e957ea566 100644
--- a/.github/workflows/prebuild-manual.yml
+++ b/.github/workflows/prebuild-manual.yml
@@ -1,6 +1,5 @@
 name: "[Prebuild] Manual PR Fanout"
-description: >-
-  Manually run prebuild publishing for a prebuild/* PR head from this repository.
+# Manually run prebuild publishing for a prebuild/* PR head from this repository.
 
 run-name: "Manual prebuild for PR #${{ inputs.pr_number }} (${{ inputs.target }})"
 
@@ -142,6 +141,7 @@ jobs:
               ],
               caipe_ui: [
                 'ui/**',
+                'scripts/npm/**',
                 'build/Dockerfile.caipe-ui',
               ],
               audit_service: [
diff --git a/build/Dockerfile.caipe-ui b/build/Dockerfile.caipe-ui
index 8e3c71aef3..19878bd7d8 100644
--- a/build/Dockerfile.caipe-ui
+++ b/build/Dockerfile.caipe-ui
@@ -13,6 +13,7 @@ WORKDIR /app
 
 # Install dependencies with cache and network resilience
 COPY ui/package.json ui/package-lock.json* ui/yarn.lock* ui/pnpm-lock.yaml* ./
+COPY scripts/npm /scripts/npm
 
 # Configure npm for better network resilience. The cache mount keeps downloaded
 # tarballs on the host between local Docker builds without baking them into the
diff --git a/docs/package.json b/docs/package.json
index 5fb29896ee..c3fc5ff034 100644
--- a/docs/package.json
+++ b/docs/package.json
@@ -12,7 +12,7 @@
     "serve": "docusaurus serve",
     "write-translations": "docusaurus write-translations",
     "write-heading-ids": "docusaurus write-heading-ids",
-    "postinstall": "node scripts/patch-gray-matter-js-yaml.mjs",
+    "postinstall": "node scripts/patch-gray-matter-js-yaml.mjs && node ../scripts/npm/patch-security-dependencies.mjs",
     "typecheck": "tsc"
   },
   "dependencies": {
diff --git a/scripts/npm/README.md b/scripts/npm/README.md
new file mode 100644
index 0000000000..0275a2d822
--- /dev/null
+++ b/scripts/npm/README.md
@@ -0,0 +1,28 @@
+# Temporary npm security backports
+
+The UI and documentation postinstall hooks run `patch-security-dependencies.mjs`.
+The UI Docker dependency stage copies this script before installing packages.
+
+- `braces@3.0.3`: limit parser nesting to 100 brace or parenthesis blocks. This
+  bounds the AST consumed by recursive compilation, expansion and stringification.
+  Ordinary patterns remain compatible; excessive nesting throws `SyntaxError`.
+  Advisory: [GHSA-vfj7-8cjw-p6xm](https://github.com/advisories/GHSA-vfj7-8cjw-p6xm).
+  Upstream discussion: [micromatch/braces#70](https://github.com/micromatch/braces/issues/70).
+- `node-forge@1.4.0`: validate the exact number of nested DigestAlgorithm elements
+  when verifying RSA signatures, including optional algorithm parameters.
+  Advisory: [GHSA-86w9-cpqp-85rv](https://github.com/advisories/GHSA-86w9-cpqp-85rv).
+  Backport source: [digitalbazaar/forge#1152](https://github.com/digitalbazaar/forge/pull/1152).
+
+Each installed copy listed in the npm lockfile is patched. Unexpected versions
+or source contents fail installation. Repeated runs verify the existing patch.
+Do not use `--ignore-scripts` for production installations.
+
+Run from `ui/` and `docs/` after `npm ci`:
+
+```sh
+node --test ../scripts/npm/*.test.mjs
+```
+
+Remove a backport and install a verified fixed version when upstream publishes
+it. Lockfile scanners continue reporting the published version; these hooks
+mitigate the installed code without concealing findings or altering versions.
diff --git a/scripts/npm/patch-security-dependencies.mjs b/scripts/npm/patch-security-dependencies.mjs
new file mode 100644
index 0000000000..6936e2fe12
--- /dev/null
+++ b/scripts/npm/patch-security-dependencies.mjs
@@ -0,0 +1,52 @@
+import { existsSync, readFileSync, writeFileSync } from "node:fs";
+import { resolve } from "node:path";
+import { pathToFileURL } from "node:url";
+
+export const braceBefore = "      stack.push(block);";
+export const braceAfter = `      if (stack.length >= 101) {
+        throw new SyntaxError('Pattern nesting exceeds maximum depth (100)');
+      }
+      stack.push(block);`;
+export const forgeBefore = "            obj.value.length !== 2) {";
+export const forgeAfter = `            obj.value.length !== 2 ||
+            obj.value[0].value.length !==
+              (('parameters' in capture) ? 2 : 1)) {`;
+
+export function patchSource(source, before, after, expected, label) {
+  // Recognize the complete patched form before searching its shared suffix.
+  if (source.split(after).length - 1 === expected &&
+      !source.split(after).join("").includes(before)) return source;
+  if (source.includes(after) || source.split(before).length - 1 !== expected) {
+    throw new Error(`Unexpected ${label} source; review the security backport`);
+  }
+  return source.split(before).join(after);
+}
+
+export function patchDependencies(directory = process.cwd()) {
+  const lock = JSON.parse(readFileSync(resolve(directory, "package-lock.json"), "utf8"));
+  const patches = {
+    braces: { version: "3.0.3", file: "lib/parse.js", before: braceBefore, after: braceAfter, count: 2 },
+    "node-forge": { version: "1.4.0", file: "lib/rsa.js", before: forgeBefore, after: forgeAfter, count: 1 },
+  };
+  for (const [packagePath, metadata] of Object.entries(lock.packages)) {
+    const name = packagePath.split("node_modules/").at(-1);
+    const patch = patches[name];
+    if (!patch || !existsSync(resolve(directory, packagePath))) continue;
+    if (metadata.version !== patch.version) {
+      throw new Error(`Review ${name} ${metadata.version} and remove or update its security backport`);
+    }
+    const installed = JSON.parse(readFileSync(resolve(directory, packagePath, "package.json"), "utf8"));
+    if (installed.name !== name || installed.version !== patch.version) {
+      throw new Error(`Unexpected installed ${name} version`);
+    }
+    const file = resolve(directory, packagePath, patch.file);
+    const source = readFileSync(file, "utf8");
+    const result = patchSource(source, patch.before, patch.after, patch.count, name);
+    if (result !== source) writeFileSync(file, result);
+    console.log(`Security backport verified: ${packagePath}`);
+  }
+}
+
+if (process.argv[1] && import.meta.url === pathToFileURL(resolve(process.argv[1])).href) {
+  patchDependencies();
+}
diff --git a/scripts/npm/prebuild-eligibility.test.mjs b/scripts/npm/prebuild-eligibility.test.mjs
new file mode 100644
index 0000000000..a100d0b3c1
--- /dev/null
+++ b/scripts/npm/prebuild-eligibility.test.mjs
@@ -0,0 +1,65 @@
+import assert from "node:assert/strict";
+import { readFileSync } from "node:fs";
+import { resolve } from "node:path";
+import test from "node:test";
+
+const root = resolve(import.meta.dirname, "../..");
+const workflow = name => readFileSync(resolve(root, ".github/workflows", name), "utf8");
+const automatic = workflow("prebuild-caipe-ui.yml");
+const manual = workflow("prebuild-manual.yml");
+const block = manual.match(/^ {10}script: \|\n((?: {12}[^\n]*\n|\n)+)/m);
+assert.ok(block, "manual prebuild metadata script must exist");
+const script = block[1].split("\n").map(line => line.slice(12)).join("\n");
+const AsyncFunction = Object.getPrototypeOf(async function () {}).constructor;
+const resolvePr = new AsyncFunction("process", "context", "github", "core", script);
+
+async function manualEligibility(file, target) {
+  const outputs = {};
+  await resolvePr(
+    { env: { PR_NUMBER: "1", TARGET: target } },
+    { repo: { owner: "example", repo: "example" }, actor: "test-user" },
+    {
+      rest: {
+        repos: { getCollaboratorPermissionLevel: async () => ({ data: { permission: "write" } }) },
+        pulls: {
+          get: async () => ({ data: {
+            number: 1, state: "open",
+            head: { repo: { full_name: "example/example" }, ref: "prebuild/example", sha: "head" },
+            base: { ref: "main", sha: "base" },
+          } }),
+          listFiles: () => {},
+        },
+      },
+      paginate: async () => [{ filename: file }],
+    },
+    { setOutput: (key, value) => { outputs[key] = value; }, info: () => {}, setFailed: assert.fail },
+  );
+  return outputs.caipe_ui_changed;
+}
+
+test("automatic prebuild trigger and inner eligibility include shared npm scripts", () => {
+  assert.match(automatic, /- 'scripts\/npm\/\*\*'/);
+  const comparison = automatic.match(/if git diff --name-only[^]*?\| grep -q \.; then/);
+  assert.ok(comparison, "prebuild changed-file comparison must exist");
+  assert.match(comparison[0], /^\s+scripts\/npm\s+\\$/m);
+});
+
+for (const target of ["all", "docker", "caipe-ui"]) {
+  test(`manual ${target} prebuild selects UI for a scripts-only change`, async () => {
+    assert.equal(await manualEligibility("scripts/npm/example.mjs", target), "true");
+    assert.equal(await manualEligibility("scripts/npm/nested/example.mjs", target), "true");
+  });
+}
+
+for (const file of ["docs/example.md", "scripts/example.mjs", "scripts/npm-example/example.mjs"]) {
+  test(`manual prebuild excludes unrelated ${file} changes from UI selection`, async () => {
+    assert.equal(await manualEligibility(file, "all"), "false");
+  });
+}
+
+test("UI retains the RBAC regression command alongside the security postinstall hook", () => {
+  const { scripts } = JSON.parse(readFileSync(resolve(root, "ui/package.json"), "utf8"));
+  assert.match(scripts["test:e2e:rbac-regression"], /^WORKFLOWS_ENABLED=true playwright test /);
+  assert.match(scripts["test:e2e:rbac-regression"], /--config=playwright\.rbac\.config\.ts$/);
+  assert.match(scripts.postinstall, /patch-security-dependencies\.mjs/);
+});
diff --git a/scripts/npm/security-backports.test.mjs b/scripts/npm/security-backports.test.mjs
new file mode 100644
index 0000000000..b08ee3521f
--- /dev/null
+++ b/scripts/npm/security-backports.test.mjs
@@ -0,0 +1,65 @@
+import assert from "node:assert/strict";
+import { createRequire } from "node:module";
+import { resolve } from "node:path";
+import test from "node:test";
+import { braceBefore, braceAfter, forgeBefore, forgeAfter, patchSource } from "./patch-security-dependencies.mjs";
+
+const require = createRequire(resolve(process.cwd(), "package.json"));
+const braces = require("braces");
+
+test("normal brace expansion and matching remain compatible", () => {
+  assert.deepEqual(braces.expand("{primary,secondary}/{1..3}"),
+    ["primary/1", "primary/2", "primary/3", "secondary/1", "secondary/2", "secondary/3"]);
+  assert.match("primary/2", new RegExp(braces.compile("{primary,secondary}/{1..3}")));
+  assert.deepEqual(braces.expand("\\{literal\\}"), ["{literal}"]);
+});
+
+for (const [open, close] of [["{", "}"], ["(", ")"], ["{(", ")}"]]) {
+  for (const operation of ["parse", "compile", "expand"]) {
+    test(`${operation} rejects excessive ${open} nesting before recursive traversal`, () => {
+      const pattern = open.repeat(3500) + "example" + close.repeat(3500);
+      // Some inputs exceed the length limit; both guards must fail with SyntaxError.
+      assert.throws(() => braces[operation](pattern), SyntaxError);
+      const bounded = open.repeat(101) + "example" + close.repeat(101);
+      assert.throws(() => braces[operation](bounded), /maximum depth/);
+      assert.doesNotThrow(() => braces[operation](open.repeat(10) + "example" + close.repeat(10)));
+    });
+  }
+}
+
+test("patching is idempotent and rejects partial patches or source drift", () => {
+  for (const [before, after, count] of [[braceBefore, braceAfter, 2], [forgeBefore, forgeAfter, 1]]) {
+    const original = Array(count).fill(before).join("\n");
+    const patched = patchSource(original, before, after, count, "example");
+    assert.equal(patchSource(patched, before, after, count, "example"), patched);
+    assert.throws(() => patchSource("unexpected source", before, after, count, "example"));
+    assert.throws(() => patchSource(patched + before, before, after, count, "example"));
+  }
+});
+
+let forge;
+try { forge = require("node-forge"); } catch (error) {
+  if (error.code !== "MODULE_NOT_FOUND") throw error;
+}
+
+test("RSA verifies valid signatures and rejects extra DigestAlgorithm elements", { skip: !forge }, () => {
+  const { publicKey, privateKey } = forge.pki.rsa.generateKeyPair({ bits: 1024, e: 65537 });
+  const hash = forge.md.sha256.create().update("example message");
+  const digest = hash.digest().getBytes();
+  assert.equal(publicKey.verify(digest, privateKey.sign(hash)), true);
+  const { Class, Type, create, oidToDer, toDer } = forge.asn1;
+  const sequence = values => create(Class.UNIVERSAL, Type.SEQUENCE, true, values);
+  const oid = create(Class.UNIVERSAL, Type.OID, false, oidToDer(forge.pki.oids.sha256).getBytes());
+  const nil = create(Class.UNIVERSAL, Type.NULL, false, "");
+  const extra = create(Class.UNIVERSAL, Type.OCTETSTRING, false, "unexpected");
+  const digestValue = create(Class.UNIVERSAL, Type.OCTETSTRING, false, digest);
+  for (const algorithm of [[oid], [oid, nil]]) {
+    const encoded = toDer(sequence([sequence(algorithm), digestValue])).getBytes();
+    assert.equal(publicKey.verify(digest, privateKey.sign(encoded, "NONE")), true);
+  }
+  for (const algorithm of [[oid, nil, extra], [oid, nil, nil]]) {
+    const encoded = toDer(sequence([sequence(algorithm), digestValue])).getBytes();
+    const signature = privateKey.sign(encoded, "NONE");
+    assert.throws(() => publicKey.verify(digest, signature), /valid RSASSA-PKCS1-v1_5/);
+  }
+});
diff --git a/ui/package-lock.json b/ui/package-lock.json
index b6d2a12347..7676b86bd4 100644
--- a/ui/package-lock.json
+++ b/ui/package-lock.json
@@ -102,7 +102,8 @@
       },
       "engines": {
         "node": ">=24.11.0 <25"
-      }
+      },
+      "hasInstallScript": true
     },
     "node_modules/@adobe/css-tools": {
       "version": "4.5.0",
diff --git a/ui/package.json b/ui/package.json
index 0f7fdb8dd3..0a30308fb0 100644
--- a/ui/package.json
+++ b/ui/package.json
@@ -27,7 +27,8 @@
     "test:e2e:rbac-live-rich-keep": "RUN_RBAC_E2E=1 RBAC_RICH_KEEP_FIXTURE=1 playwright test e2e/rbac/rbac-rich-local-regression-live.spec.ts --config=playwright.rbac.config.ts",
     "test:e2e:rbac-live-rich-cleanup": "RUN_RBAC_E2E=1 playwright test e2e/rbac/rbac-rich-local-regression-live.spec.ts --config=playwright.rbac.config.ts",
     "test:e2e:rbac-live-full": "RUN_RBAC_E2E=1 playwright test e2e/rbac/openfga-live.spec.ts e2e/rbac/mcp-server-create-live.spec.ts e2e/rbac/resource-lifecycle-live.spec.ts e2e/rbac/credential-team-sharing.spec.ts e2e/rbac/rbac-rich-local-regression-live.spec.ts --config=playwright.rbac.config.ts",
-    "test:e2e:token-refresh": "RUN_RBAC_E2E=1 playwright test e2e/rbac/token-refresh.spec.ts --config=playwright.rbac.config.ts"
+    "test:e2e:token-refresh": "RUN_RBAC_E2E=1 playwright test e2e/rbac/token-refresh.spec.ts --config=playwright.rbac.config.ts",
+    "postinstall": "node ../scripts/npm/patch-security-dependencies.mjs"
   },
   "dependencies": {
     "@aws-sdk/client-kms": "3.1119.0",