.github/workflows/ci.yml

@@ -34,3 +34,8 @@ jobs:
       # Fail the build if any dependency is not open source.
       - name: Licence compliance (make licenses)
         run: make licenses
+
+      # Fail the build if a vendored JS bundle drifted from its manifest or a
+      # pinned version has a known vulnerability (queries the OSV database).
+      - name: Bundled JS security (make deps-check)
+        run: make deps-check

Makefile

@@ -1,4 +1,4 @@
-.PHONY: setup format format-check analyze test test-contracts test-preview test-export test-state test-services test-presenter deps-outdated licenses check check-full help
+.PHONY: setup format format-check analyze test test-contracts test-preview test-export test-state test-services test-presenter deps-outdated deps-check licenses check check-full help
 
 help:
 	@echo "OciDeck quality targets:"
@@ -11,6 +11,7 @@ help:
 	@echo "  make test-services   Caption/description/image service tests."
 	@echo "  make test-presenter  Fullscreen presenter interaction tests."
 	@echo "  make deps-outdated   Advisory dependency freshness report."
+	@echo "  make deps-check      Verify vendored JS bundles vs manifest + OSV CVEs."
 	@echo "  make licenses        Verify all dependencies use open-source licences."
 
 # Install Flutter/Dart dependencies.
@@ -106,6 +107,18 @@ deps-outdated:
 	@echo "Failure means: inspect network/tooling first; outdated packages are not necessarily regressions."
 	flutter pub outdated
 
+# Security gate for the vendored JS bundles inlined into the HTML export.
+# Verifies each file still matches assets/web_export/MANIFEST.json (sha256) and
+# queries the OSV database for known vulnerabilities in the pinned versions.
+deps-check:
+	@echo "== OciDeck check: bundled JavaScript =="
+	@echo "Command: dart run tool/check_bundled_js.dart"
+	@echo "Covers: integrity (sha256 vs manifest) + known CVEs (OSV) for marked,"
+	@echo "        highlight.js, DOMPurify, mermaid and MathJax."
+	@echo "Failure means: a bundle drifted from the manifest, or a pinned version"
+	@echo "        now has a known vulnerability — upgrade it and refresh the manifest."
+	dart run tool/check_bundled_js.dart
+
 # Open-source licence compliance check for all resolved dependencies.
 licenses:
 	@echo "== OciDeck check: licences =="
@@ -120,6 +133,6 @@ check: format-check analyze test
 	@echo "Validated: formatting, static analysis, and the full Flutter test suite."
 
 # Extended local check with advisory dependency freshness after the required gate.
-check-full: check licenses deps-outdated
+check-full: check licenses deps-check deps-outdated
 	@echo "== OciDeck extended check complete =="
-	@echo "Validated: required quality gate, licence compliance, and dependency freshness."
+	@echo "Validated: required quality gate, licence compliance, bundled-JS CVEs, and dependency freshness."

THIRD_PARTY_NOTICES.md

@@ -14,10 +14,16 @@ Shipped inside the app and embedded into the **offline HTML export**
 | --- | --- | --- |
 | [marked](https://github.com/markedjs/marked) | Markdown → HTML in the export | MIT |
 | [highlight.js](https://github.com/highlightjs/highlight.js) | Code highlighting in the export | BSD-3-Clause |
-| [Mermaid](https://github.com/mermaid-js/mermaid) | Diagrams in the export | MIT (bundles [DOMPurify](https://github.com/cure53/DOMPurify), Apache-2.0 / MPL-2.0) |
+| [DOMPurify](https://github.com/cure53/DOMPurify) | Sanitises the rendered Markdown before it hits the DOM in the export | Apache-2.0 / MPL-2.0 |
+| [Mermaid](https://github.com/mermaid-js/mermaid) | Diagrams in the export | MIT |
 | [MathJax](https://github.com/mathjax/MathJax) (`tex-svg.js`) | Math rendering in the export | Apache-2.0 |
 | [EB Garamond](https://github.com/octaviopardo/EBGaramond12) font | Bundled deck font | SIL Open Font License 1.1 |
 
+The exact pinned version, source URL and SHA-256 of every vendored JS bundle
+live in [`assets/web_export/MANIFEST.json`](assets/web_export/MANIFEST.json).
+`make deps-check` verifies each file still matches that manifest and queries the
+[OSV](https://osv.dev) database for known vulnerabilities.
+
 ## Vendored (forked) plugins
 
 Kept in `third_party/` and wired in via `pubspec.yaml` (path dependency /

assets/web_export/MANIFEST.json

@@ -0,0 +1,46 @@
+{
+  "_comment": "Pinned inventory of the vendored JavaScript bundles inlined into the offline HTML export (see lib/services/marp_html_service.dart). Each entry records the npm package + exact version so `make deps-check` can query the OSV vulnerability database, and a sha256 so the same check can prove the on-disk file still matches this manifest (tamper / accidental-replacement guard). When you intentionally upgrade a bundle, update its version, source and sha256 here in the same commit.",
+  "ecosystem": "npm",
+  "bundles": [
+    {
+      "file": "marked.min.js",
+      "npm": "marked",
+      "version": "18.0.5",
+      "sha256": "2dc4769dfde29f51c7aca1a539c6407c789c8ea644cf8b7d01ded28a9c1d800b",
+      "source": "https://cdn.jsdelivr.net/npm/marked@18.0.5/lib/marked.umd.js",
+      "license": "MIT"
+    },
+    {
+      "file": "highlight.min.js",
+      "npm": "highlight.js",
+      "version": "11.11.1",
+      "sha256": "c4a399dd6f488bc97a3546e3476747b3e714c99c57b9473154c6fb8d259b9381",
+      "source": "https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.11.1/highlight.min.js",
+      "license": "BSD-3-Clause"
+    },
+    {
+      "file": "purify.min.js",
+      "npm": "dompurify",
+      "version": "3.4.9",
+      "sha256": "3c16cc90eb152b823b71b8585cd79e7fb7cd7a380157a800dfbd9459aad5f726",
+      "source": "https://cdn.jsdelivr.net/npm/dompurify@3.4.9/dist/purify.min.js",
+      "license": "Apache-2.0 OR MPL-2.0"
+    },
+    {
+      "file": "mermaid.min.js",
+      "npm": "mermaid",
+      "version": "10.9.6",
+      "sha256": "eda3a0ad572bbe69a318c1be0163e8233dd824f3f12939e5168feba207767151",
+      "source": "https://cdn.jsdelivr.net/npm/mermaid@10.9.6/dist/mermaid.min.js",
+      "license": "MIT"
+    },
+    {
+      "file": "tex-svg.js",
+      "npm": "mathjax",
+      "version": "3.2.2",
+      "sha256": "d4295dc33744836935c1399feece5159577b34c5c8ffb9f1c6324cd82e03a882",
+      "source": "https://cdn.jsdelivr.net/npm/mathjax@3.2.2/es5/tex-svg.js",
+      "license": "Apache-2.0"
+    }
+  ]
+}

lib/services/marp_html_service.dart

@@ -6,6 +6,7 @@ import 'package:flutter/services.dart' show rootBundle;
 
 import '../models/chart.dart';
 import '../models/settings.dart';
+import '../utils/log.dart';
 
 /// Builds a single, self-contained HTML file from a deck's Marp Markdown.
 ///
@@ -38,6 +39,7 @@ class MarpHtmlService {
   /// colours and font so the export matches the in-app / PDF look.
   Future<String> build(String deckMarkdown, {ThemeProfile? theme}) async {
     final marked = await loadAsset('$_assetDir/marked.min.js');
+    final purify = await loadAsset('$_assetDir/purify.min.js');
     final hljs = await loadAsset('$_assetDir/highlight.min.js');
     final hljsCss = await loadAsset('$_assetDir/highlight.css');
     final mathjax = await loadAsset('$_assetDir/tex-svg.js');
@@ -61,6 +63,7 @@ class MarpHtmlService {
         '<style>$css\n$hljsCss</style>'
         '<script>$_mathjaxConfig</script>'
         '${inline(marked)}'
+        '${inline(purify)}'
         '${inline(hljs)}'
         '${inline(mathjax)}'
         '${inline(mermaid)}'
@@ -97,11 +100,16 @@ class MarpHtmlService {
   }
 
   /// Neutralise any `</script` inside inlined content so it can't break out of
-  /// the surrounding <script> element. Safe for both JS (string contexts) and
+  /// the surrounding <script> element. Case-insensitive — `</ScRiPt>` must not
-  /// the embedded Markdown payloads.
+  /// slip through. Safe for both JS (string contexts) and the embedded Markdown
-  static String _guard(String s) => s
+  /// payloads.
-      .replaceAll('</script', r'<\/script')
+  static final RegExp _scriptClose = RegExp(
-      .replaceAll('</SCRIPT', r'<\/SCRIPT');
+    r'</(script)',
+    caseSensitive: false,
+  );
+
+  static String _guard(String s) =>
+      s.replaceAllMapped(_scriptClose, (m) => '<\\/${m.group(1)}');
 
   // ── Charts → inline SVG ────────────────────────────────────────────────────
 
@@ -563,7 +571,9 @@ class MarpHtmlService {
     final range = (rawHi - rawLo).abs();
     final r = range <= 0 ? 1.0 : range;
     final rawStep = r / 4;
-    final mag = math.pow(10, (math.log(rawStep) / math.ln10).floor()).toDouble();
+    final mag = math
+        .pow(10, (math.log(rawStep) / math.ln10).floor())
+        .toDouble();
     final norm = rawStep / mag;
     final niceNorm = norm < 1.5
         ? 1.0
@@ -640,7 +650,8 @@ class MarpHtmlService {
       return "@font-face{font-family:'EB Garamond';font-weight:400 800;"
           "font-style:normal;src:url(data:font/ttf;base64,$b64) "
           "format('truetype');}";
-    } catch (_) {
+    } catch (e) {
+      logWarning('MarpHtmlService._ebGaramondFontFace: load font asset', e);
       return ''; // Fall back to the CSS font stack if the asset is missing.
     }
   }
@@ -672,7 +683,11 @@ body{background:#1e1e1e;font-family:-apple-system,"Segoe UI",Roboto,Helvetica,Ar
     var holder=sec.querySelector('script[type="text/markdown"]');
     var src=holder?holder.textContent:'';
     var div=document.createElement('div');div.className='content';
-    div.innerHTML=window.marked?marked.parse(src):src;
+    var html=window.marked?marked.parse(src):src;
+    // Sanitise rendered Markdown before it touches the DOM: a deck must not be
+    // able to run script/onerror/javascript: payloads when the export is opened.
+    // If the sanitiser somehow isn't present, fail closed to plain text.
+    if(window.DOMPurify){div.innerHTML=DOMPurify.sanitize(html);}else{div.textContent=src;}
     sec.innerHTML='';sec.appendChild(div);
   });
   document.querySelectorAll('code.language-mermaid').forEach(function(code){

tool/check_bundled_js.dart

@@ -0,0 +1,178 @@
+// Security gate for the vendored JavaScript bundles that get inlined into the
+// offline HTML export (marked, highlight.js, DOMPurify, mermaid, MathJax — see
+// lib/services/marp_html_service.dart). Unlike Dart packages, these are checked
+// into the repo by hand and are not covered by `flutter pub outdated`, so this
+// tool is their dedicated safety net.
+//
+//   dart run tool/check_bundled_js.dart     (or: make deps-check)
+//
+// It does two independent things, both of which can fail the build:
+//
+//   1. Integrity (offline, deterministic): every file listed in
+//      assets/web_export/MANIFEST.json must still hash to the recorded sha256.
+//      Catches a bundle that was swapped, truncated, or edited without the
+//      manifest (and therefore this review) being updated.
+//
+//   2. Known vulnerabilities (online): each pinned package@version is queried
+//      against the OSV database (https://osv.dev). Any advisory fails the gate
+//      so we learn a vendored bundle needs upgrading the moment a CVE lands —
+//      not at the next manual audit.
+//
+// Exit codes:  0 = clean   1 = integrity mismatch or known vulnerability
+//              2 = could not run the check (missing manifest / no network)
+//
+// Run it routinely (it is wired into `make deps-check` and CI). When it flags a
+// vulnerability, upgrade the bundle, refresh its version + sha256 in
+// MANIFEST.json, and update THIRD_PARTY_NOTICES.md in the same commit.
+
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:crypto/crypto.dart';
+
+const _manifestPath = 'assets/web_export/MANIFEST.json';
+const _assetDir = 'assets/web_export';
+const _osvUrl = 'https://api.osv.dev/v1/query';
+
+Future<void> main(List<String> args) async {
+  final offline = args.contains('--offline');
+
+  final manifestFile = File(_manifestPath);
+  if (!manifestFile.existsSync()) {
+    stderr.writeln('No $_manifestPath — cannot check the bundled JS.');
+    exit(2);
+  }
+
+  final manifest =
+      jsonDecode(manifestFile.readAsStringSync()) as Map<String, dynamic>;
+  final ecosystem = (manifest['ecosystem'] as String?) ?? 'npm';
+  final bundles = (manifest['bundles'] as List).cast<Map<String, dynamic>>();
+
+  stdout.writeln('== OciDeck check: bundled JavaScript ==');
+  stdout.writeln('Manifest: $_manifestPath  (${bundles.length} bundles)\n');
+
+  final integrityProblems = <String>[];
+  final vulnProblems = <String>[];
+  var networkFailed = false;
+
+  for (final b in bundles) {
+    final file = b['file'] as String;
+    final npm = b['npm'] as String;
+    final version = b['version'] as String;
+    final expected = (b['sha256'] as String).toLowerCase();
+    final path = '$_assetDir/$file';
+
+    // --- 1. Integrity -------------------------------------------------------
+    final f = File(path);
+    String integrity;
+    if (!f.existsSync()) {
+      integrity = 'MISSING FILE';
+      integrityProblems.add('$file — file not found at $path');
+    } else {
+      final actual = sha256.convert(f.readAsBytesSync()).toString();
+      if (actual == expected) {
+        integrity = 'sha256 ok';
+      } else {
+        integrity = 'SHA256 MISMATCH';
+        integrityProblems.add(
+          '$file — sha256 differs from manifest\n'
+          '      expected $expected\n'
+          '      actual   $actual',
+        );
+      }
+    }
+
+    // --- 2. Known vulnerabilities (OSV) ------------------------------------
+    String vulnStatus;
+    if (offline) {
+      vulnStatus = 'skipped (--offline)';
+    } else {
+      final r = await _queryOsv(ecosystem, npm, version);
+      if (r == null) {
+        vulnStatus = 'OSV UNREACHABLE';
+        networkFailed = true;
+      } else if (r.isEmpty) {
+        vulnStatus = 'no known CVEs';
+      } else {
+        vulnStatus = '${r.length} ADVISORY(IES): ${r.join(', ')}';
+        vulnProblems.add('$npm@$version → ${r.join(', ')}');
+      }
+    }
+
+    stdout.writeln('  $npm@$version  ($file)');
+    stdout.writeln('      integrity : $integrity');
+    stdout.writeln('      osv       : $vulnStatus');
+  }
+
+  stdout.writeln('');
+
+  if (integrityProblems.isEmpty && vulnProblems.isEmpty && !networkFailed) {
+    stdout.writeln(
+      'OK — all bundles match the manifest and have no known CVEs.',
+    );
+    exit(0);
+  }
+
+  if (integrityProblems.isNotEmpty) {
+    stderr.writeln('INTEGRITY — ${integrityProblems.length} problem(s):');
+    for (final p in integrityProblems) {
+      stderr.writeln('  $p');
+    }
+    stderr.writeln(
+      '  A mismatch means a bundle changed without MANIFEST.json being updated.\n'
+      '  If the change was intentional, refresh the version + sha256 there.',
+    );
+  }
+
+  if (vulnProblems.isNotEmpty) {
+    stderr.writeln('\nVULNERABILITIES — ${vulnProblems.length} bundle(s):');
+    for (final p in vulnProblems) {
+      stderr.writeln('  $p');
+    }
+    stderr.writeln(
+      '  Upgrade the bundle, then update MANIFEST.json + THIRD_PARTY_NOTICES.md.\n'
+      '  Advisory detail: https://osv.dev/<ID>',
+    );
+  }
+
+  if (integrityProblems.isNotEmpty || vulnProblems.isNotEmpty) exit(1);
+
+  // Only network trouble, nothing actually wrong with the bundles.
+  stderr.writeln(
+    'COULD NOT VERIFY CVEs — OSV was unreachable. Integrity passed.\n'
+    '  Re-run with network access, or `--offline` to check integrity only.',
+  );
+  exit(2);
+}
+
+/// Returns the list of OSV advisory IDs affecting [name]@[version], an empty
+/// list if there are none, or null if the database could not be reached.
+Future<List<String>?> _queryOsv(
+  String ecosystem,
+  String name,
+  String version,
+) async {
+  final client = HttpClient()..connectionTimeout = const Duration(seconds: 15);
+  try {
+    final req = await client.postUrl(Uri.parse(_osvUrl));
+    req.headers.contentType = ContentType.json;
+    req.write(
+      jsonEncode({
+        'package': {'name': name, 'ecosystem': ecosystem},
+        'version': version,
+      }),
+    );
+    final resp = await req.close().timeout(const Duration(seconds: 20));
+    if (resp.statusCode != 200) return null;
+    final body = await resp.transform(utf8.decoder).join();
+    final data = jsonDecode(body) as Map<String, dynamic>;
+    final vulns = (data['vulns'] as List?) ?? const [];
+    return vulns
+        .map((v) => (v as Map<String, dynamic>)['id'] as String)
+        .toList();
+  } on Object {
+    return null;
+  } finally {
+    client.close(force: true);
+  }
+}