diff --git a/apps/api/package.json b/apps/api/package.json
index dc1e93d..646850c 100644
--- a/apps/api/package.json
+++ b/apps/api/package.json
@@ -48,6 +48,7 @@
     "reflect-metadata": "^0.2.0",
     "rxjs": "^7.0.0",
     "tsdav": "2.2.2",
+    "undici": "7.28.0",
     "xlsx": "^0.18.5"
   },
   "devDependencies": {
diff --git a/apps/api/src/favorites/dto/reorder-favorites.dto.ts b/apps/api/src/favorites/dto/reorder-favorites.dto.ts
new file mode 100644
index 0000000..b1157d0
--- /dev/null
+++ b/apps/api/src/favorites/dto/reorder-favorites.dto.ts
@@ -0,0 +1,28 @@
+import {
+  ArrayMaxSize,
+  ArrayMinSize,
+  ArrayUnique,
+  IsArray,
+  IsUUID,
+} from 'class-validator';
+
+/**
+ * DTO for `PUT /favorites/order` (260917-jdd).
+ *
+ * `ids` is the FULL id list of a widget's favorites, in the desired display
+ * order — the service requires an exact match against the caller's existing
+ * favorites for this widget (no partial reorder, no foreign/unknown ids).
+ * `ArrayMaxSize(500)` is a DoS cap for the `updateMany` loop inside the
+ * transaction (T-JDD-05); a widget has a handful of links in practice.
+ */
+export class ReorderFavoritesDto {
+  @IsUUID()
+  widgetId!: string;
+
+  @IsArray()
+  @ArrayMinSize(1)
+  @ArrayMaxSize(500)
+  @ArrayUnique()
+  @IsUUID('all', { each: true })
+  ids!: string[];
+}
diff --git a/apps/api/src/favorites/favorites.controller.ts b/apps/api/src/favorites/favorites.controller.ts
index a8b2cb5..a49cb5f 100644
--- a/apps/api/src/favorites/favorites.controller.ts
+++ b/apps/api/src/favorites/favorites.controller.ts
@@ -8,12 +8,14 @@ import {
   ParseUUIDPipe,
   Patch,
   Post,
+  Put,
   Query,
   Req,
   Res,
 } from '@nestjs/common';
 import { Request, Response } from 'express';
 import { CreateFavoriteDto } from './dto/create-favorite.dto';
+import { ReorderFavoritesDto } from './dto/reorder-favorites.dto';
 import { UpdateFavoriteDto } from './dto/update-favorite.dto';
 import { FavoritesService } from './favorites.service';
 
@@ -35,6 +37,8 @@ import { FavoritesService } from './favorites.service';
  * Routes:
  * - GET  /favorites?widgetId=   — list favorites for a widget instance
  * - POST /favorites             — create a favorite (triggers server-side icon discovery)
+ * - PUT  /favorites/order       — reorder favorites for a widget instance (260917-jdd)
+ * - GET  /favorites/:id/icon    — stream a favorite's stored icon bytes
  * - PATCH /favorites/:id        — update a favorite (ownership verified in service)
  * - DELETE /favorites/:id       — delete a favorite (ownership verified in service)
  */
@@ -77,6 +81,23 @@ export class FavoritesController {
     return this.favoritesService.create(tenantId, userId, dto);
   }
 
+  /**
+   * PUT /favorites/order — persists the display order for a widget's
+   * favorites (260917-jdd). Declared BEFORE the `:id` routes below on
+   * purpose (NestJS route order — a later `:id` route would otherwise
+   * shadow the literal segment "order"; precedent tenders.controller.ts
+   * Z. 636-648).
+   */
+  @Put('order')
+  async reorder(
+    @Body() dto: ReorderFavoritesDto,
+    @Req() req: Request,
+  ) {
+    const { userId, tenantId } = this.extractContext(req);
+
+    return this.favoritesService.reorder(tenantId, userId, dto);
+  }
+
   /**
    * GET /favorites/:id/icon — streams the stored icon bytes for a favorite
    * owned by the caller, from Tessera's own origin. This avoids the browser
@@ -101,6 +122,12 @@ export class FavoritesController {
 
     res.setHeader('Content-Type', contentType);
     res.setHeader('Cache-Control', 'public, max-age=86400');
+    // 260917-jdd: die Bytes kommen jetzt auch von Hosts ohne gueltiges
+    // Zertifikat. Als <img>-Unterressource ignoriert der Browser diese
+    // Header, aber ein direkt im Tab geoeffnetes SVG laeuft damit ohne
+    // Skript und ohne Tessera-Origin (T-JDD-02).
+    res.setHeader('X-Content-Type-Options', 'nosniff');
+    res.setHeader('Content-Security-Policy', "default-src 'none'; sandbox");
     res.send(body);
   }
 
diff --git a/apps/api/src/favorites/favorites.service.spec.ts b/apps/api/src/favorites/favorites.service.spec.ts
index 8feaf6d..ffd0877 100644
--- a/apps/api/src/favorites/favorites.service.spec.ts
+++ b/apps/api/src/favorites/favorites.service.spec.ts
@@ -1,7 +1,7 @@
 import { BadRequestException, HttpException, NotFoundException } from '@nestjs/common';
 import { beforeEach, describe, expect, it, vi } from 'vitest';
 import { FavoritesService } from './favorites.service';
-import { forTenant } from '../prisma/prisma-tenant.extension';
+import { forTenant, withTenantTransaction } from '../prisma/prisma-tenant.extension';
 
 /**
  * FavoritesService.spec — NEU (260911-gwh). Der Bereich `favorites` hatte
@@ -14,9 +14,18 @@ import { forTenant } from '../prisma/prisma-tenant.extension';
  * Modellzugriff scheitert mit "Cannot read properties of undefined" (die
  * dkv-Form der Falsifizierung, siehe auth.service.spec.ts:280). Der
  * GEBUNDENE Klient hat ausschliesslich `favoriteLink`/`widgetInstance`.
+ *
+ * 260917-jdd: `withTenantTransaction` kommt zum Mock hinzu (Muster
+ * groups.service.spec.ts Z. 30-35/296-299) — `prisma.__withTenantTransaction`
+ * reicht den gebundenen Klienten als `tx` durch und protokolliert den
+ * Aufruf. Der Fake bekommt zusaetzlich `updateMany` auf `favoriteLink` fuer
+ * `reorder()`.
  */
 vi.mock('../prisma/prisma-tenant.extension', () => ({
   forTenant: vi.fn((unboundClient: any, tenantId: string) => unboundClient.__makeBoundClient(tenantId)),
+  withTenantTransaction: vi.fn((unboundClient: any, tenantId: string, fn: (tx: any) => any) =>
+    unboundClient.__withTenantTransaction(tenantId, fn),
+  ),
 }));
 
 interface FakeFavoriteRow {
@@ -40,7 +49,7 @@ interface FakeWidgetRow {
 
 interface BoundCall {
   tenantId: string;
-  model: 'favoriteLink' | 'widgetInstance';
+  model: 'favoriteLink' | 'widgetInstance' | '$transaction';
   method: string;
 }
 
@@ -117,6 +126,20 @@ function makeFakePrisma(favoriteRows: FakeFavoriteRow[] = [], widgetRows: FakeWi
         favorites.delete(where.id);
         return row;
       },
+      // 260917-jdd: reorder() — filtert nach tenantId sowie, falls in
+      // `where` vorhanden, id/userId/widgetId; wendet `data` auf jede
+      // Treffer-Zeile an; liefert { count }.
+      updateMany: async ({ where, data }: any) => {
+        boundCallLog.push({ tenantId, model: 'favoriteLink', method: 'updateMany' });
+        let rows = Array.from(favorites.values()).filter((f) => f.tenantId === tenantId);
+        if (where?.id) rows = rows.filter((f) => f.id === where.id);
+        if (where?.userId) rows = rows.filter((f) => f.userId === where.userId);
+        if (where?.widgetId) rows = rows.filter((f) => f.widgetId === where.widgetId);
+        for (const row of rows) {
+          favorites.set(row.id, { ...row, ...data, updatedAt: new Date() });
+        }
+        return { count: rows.length };
+      },
     };
   }
 
@@ -146,6 +169,10 @@ function makeFakePrisma(favoriteRows: FakeFavoriteRow[] = [], widgetRows: FakeWi
         widgetInstance: makeScopedWidgetInstance(tenantId),
       };
     },
+    __withTenantTransaction(tenantId: string, fn: (tx: any) => any) {
+      boundCallLog.push({ tenantId, model: '$transaction', method: 'withTenantTransaction' });
+      return fn(fake.__makeBoundClient(tenantId));
+    },
   };
   return fake;
 }
@@ -505,4 +532,97 @@ describe('FavoritesService — Bindung an forTenant() (260911-gwh)', () => {
       }
     });
   });
+
+  describe('reorder (260917-jdd)', () => {
+    const makeAltbestand = () =>
+      makeFakePrisma([
+        { id: 'f1', userId: 'user-a1', tenantId: 't1', widgetId: 'widget-a1', title: 'A', url: 'https://a.invalid', iconUrl: null, position: 0 },
+        { id: 'f2', userId: 'user-a1', tenantId: 't1', widgetId: 'widget-a1', title: 'B', url: 'https://b.invalid', iconUrl: null, position: 0 },
+        { id: 'f3', userId: 'user-a1', tenantId: 't1', widgetId: 'widget-a1', title: 'C', url: 'https://c.invalid', iconUrl: null, position: 0 },
+        { id: 'f9', userId: 'user-a2', tenantId: 't1', widgetId: 'widget-a1', title: 'D', url: 'https://d.invalid', iconUrl: null, position: 0 },
+      ]);
+
+    it('setzt position 0/1/2 in der uebergebenen Reihenfolge und liefert die Liste so sortiert', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      const result = await service.reorder('t1', 'user-a1', {
+        widgetId: 'widget-a1',
+        ids: ['f3', 'f1', 'f2'],
+      } as any);
+
+      expect(result.map((r: any) => r.id)).toEqual(['f3', 'f1', 'f2']);
+      expect(prisma.__favorites.get('f3').position).toBe(0);
+      expect(prisma.__favorites.get('f1').position).toBe(1);
+      expect(prisma.__favorites.get('f2').position).toBe(2);
+      expect(prisma.__favorites.get('f9').position).toBe(0);
+      expect(vi.mocked(withTenantTransaction)).toHaveBeenCalledWith(prisma, 't1', expect.any(Function));
+      expectBoundCall(prisma, 't1', 'favoriteLink', 'updateMany');
+    });
+
+    it('fremde id (user-a2) -> BadRequestException, KEINE Position geaendert', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      await expect(
+        service.reorder('t1', 'user-a1', { widgetId: 'widget-a1', ids: ['f3', 'f1', 'f9'] } as any),
+      ).rejects.toThrow(BadRequestException);
+      expect(prisma.__favorites.get('f1').position).toBe(0);
+      expect(prisma.__favorites.get('f2').position).toBe(0);
+      expect(prisma.__favorites.get('f3').position).toBe(0);
+    });
+
+    it('unbekannte id -> BadRequestException', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      await expect(
+        service.reorder('t1', 'user-a1', { widgetId: 'widget-a1', ids: ['f3', 'f1', 'f-fehlt'] } as any),
+      ).rejects.toThrow(BadRequestException);
+    });
+
+    it('Teilmenge (2 von 3) -> BadRequestException', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      await expect(
+        service.reorder('t1', 'user-a1', { widgetId: 'widget-a1', ids: ['f1', 'f2'] } as any),
+      ).rejects.toThrow(BadRequestException);
+    });
+
+    it('doppelte ids -> BadRequestException OHNE withTenantTransaction-Aufruf', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      vi.mocked(withTenantTransaction).mockClear();
+      await expect(
+        service.reorder('t1', 'user-a1', { widgetId: 'widget-a1', ids: ['f1', 'f1', 'f2'] } as any),
+      ).rejects.toThrow(BadRequestException);
+      expect(vi.mocked(withTenantTransaction).mock.calls.length).toBe(0);
+    });
+
+    it('fremder Mandant (t2 auf t1-Zeilen) -> BadRequestException, Positionen unveraendert', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      await expect(
+        service.reorder('t2', 'user-a1', { widgetId: 'widget-a1', ids: ['f1', 'f2', 'f3'] } as any),
+      ).rejects.toThrow(BadRequestException);
+      expect(prisma.__favorites.get('f1').position).toBe(0);
+      expect(prisma.__favorites.get('f2').position).toBe(0);
+      expect(prisma.__favorites.get('f3').position).toBe(0);
+    });
+
+    it('Wachhund: 0 forTenant-Aufrufe, genau 1 withTenantTransaction-Aufruf fuer den Happy Path', async () => {
+      const prisma = makeAltbestand();
+      const service = new FavoritesService(prisma as any, makeIconDiscovery() as any);
+
+      vi.mocked(forTenant).mockClear();
+      vi.mocked(withTenantTransaction).mockClear();
+      await service.reorder('t1', 'user-a1', { widgetId: 'widget-a1', ids: ['f3', 'f1', 'f2'] } as any);
+
+      expect(vi.mocked(forTenant).mock.calls.length).toBe(0);
+      expect(vi.mocked(withTenantTransaction).mock.calls.length).toBe(1);
+    });
+  });
 });
diff --git a/apps/api/src/favorites/favorites.service.ts b/apps/api/src/favorites/favorites.service.ts
index 413b9fd..3185102 100644
--- a/apps/api/src/favorites/favorites.service.ts
+++ b/apps/api/src/favorites/favorites.service.ts
@@ -6,8 +6,9 @@ import {
   NotFoundException,
 } from '@nestjs/common';
 import { PrismaService } from '../prisma/prisma.service';
-import { forTenant } from '../prisma/prisma-tenant.extension';
+import { forTenant, withTenantTransaction } from '../prisma/prisma-tenant.extension';
 import { CreateFavoriteDto } from './dto/create-favorite.dto';
+import { ReorderFavoritesDto } from './dto/reorder-favorites.dto';
 import { UpdateFavoriteDto } from './dto/update-favorite.dto';
 import { IconDiscoveryService, normalizeUrl } from './icon-discovery.service';
 
@@ -37,6 +38,8 @@ import { IconDiscoveryService, normalizeUrl } from './icon-discovery.service';
  * - Every query is scoped by userId (prevents cross-user access).
  * - list() additionally scopes by widgetId so each widget instance has its own set.
  * - update() and remove() verify userId ownership before mutating.
+ * - reorder() runs as one withTenantTransaction() (T-JDD-03) and scopes
+ *   every updateMany by userId AND widgetId (see reorder() doc below).
  *
  * `create()` prueft zusaetzlich, dass das Ziel-Widget dem Aufrufer gehoert
  * (T-GWH-05): der Fremdschluessel `FavoriteLink.widgetId` prueft an der
@@ -171,6 +174,74 @@ export class FavoritesService {
     await tenantPrisma.favoriteLink.delete({ where: { id } });
   }
 
+  /**
+   * Persists the display order of a user's favorites for one widget
+   * instance (260917-jdd, PUT /favorites/order).
+   *
+   * Laeuft als EINE Transaktion ueber `withTenantTransaction()` — die
+   * einzige gemessene atomare Form fuer einen Mehrschritt-Zugriff
+   * (prisma-tenant.extension.ts Z. 33-49/104-109); die Array-Form von
+   * `$transaction` auf einem mit `forTenant()` gebundenen Klienten ist
+   * gemessen NICHT atomar, die interaktive Form auf dem gebundenen Klienten
+   * faellt unter Last aus (siehe dortige Messung). `withTenantTransaction()`
+   * setzt KEINE Benutzerdimension in der Sitzung (nur `app.current_tenant`)
+   * — die Regel auf `FavoriteLink` faellt deshalb in ihren `IS NULL`-Zweig
+   * und zeigt den ganzen Mandanten. Darum traegt JEDE Bedingung unten
+   * `userId` UND `widgetId` selbst (zweites Netz, wie der Kopfkommentar
+   * dieser Klasse es fuer alle Methoden vorsieht).
+   *
+   * `updateMany` statt `update({ where: { id } })`, weil `update` nur nach
+   * `id` filtern koennte — der Ownership-Check muesste dann als separater
+   * Lese-Schritt VOR dem Schreiben stehen, mit derselben TOCTOU-Luecke wie
+   * ein fehlendes zweites Netz. `updateMany` traegt die Bedingung direkt in
+   * der Schreiboperation und liefert `count`, das sofort geprueft wird.
+   *
+   * Existenzorakel-Vermeidung (T-JDD-06): EINE BadRequestException mit
+   * DERSELBEN Meldung fuer fremde id, unbekannte id, Teilmenge sowie
+   * fremdes/unbekanntes Widget oder Mandant — kein Fall verraet, welcher
+   * Grund zutraf (Muster T-GWH-05).
+   *
+   * Altbestand: alle Zeilen mit `position = 0` (vor diesem Plan gab es
+   * keine Sortierung) normalisiert sich beim ERSTEN Aufruf zu `0..n-1` —
+   * kein Migrations- oder Sonderpfad noetig.
+   */
+  async reorder(tenantId: string, userId: string, dto: ReorderFavoritesDto) {
+    if (new Set(dto.ids).size !== dto.ids.length) {
+      throw new BadRequestException('ids must match the favorites of this widget exactly');
+    }
+
+    return withTenantTransaction(this.prisma, tenantId, async (tx: any) => {
+      const existing = await tx.favoriteLink.findMany({
+        where: { userId, widgetId: dto.widgetId },
+        select: { id: true },
+      });
+      const existingIds = new Set(existing.map((r: { id: string }) => r.id));
+
+      if (
+        existing.length !== dto.ids.length ||
+        dto.ids.some((id) => !existingIds.has(id))
+      ) {
+        throw new BadRequestException('ids must match the favorites of this widget exactly');
+      }
+
+      for (const [index, id] of dto.ids.entries()) {
+        const { count } = await tx.favoriteLink.updateMany({
+          where: { id, userId, widgetId: dto.widgetId },
+          data: { position: index },
+        });
+
+        if (count !== 1) {
+          throw new BadRequestException('ids must match the favorites of this widget exactly');
+        }
+      }
+
+      return tx.favoriteLink.findMany({
+        where: { userId, widgetId: dto.widgetId },
+        orderBy: [{ position: 'asc' }, { title: 'asc' }],
+      });
+    });
+  }
+
   /**
    * Fetches the raw bytes of a favorite's stored icon, scoped to the
    * requesting user (T-08-06 — same ownership check as update/remove).
diff --git a/apps/api/src/favorites/icon-discovery.service.spec.ts b/apps/api/src/favorites/icon-discovery.service.spec.ts
index 094c99a..0693da0 100644
--- a/apps/api/src/favorites/icon-discovery.service.spec.ts
+++ b/apps/api/src/favorites/icon-discovery.service.spec.ts
@@ -1,4 +1,22 @@
 import { afterEach, describe, expect, it, vi } from 'vitest';
+
+/**
+ * 260917-jdd — `undici` wird gemockt, damit KEIN Test tatsaechlich ins Netz
+ * geht: die produktive Datei ruft ab jetzt `undiciFetch` statt des globalen
+ * `fetch` auf, mit einem Modul-Singleton-`Agent` als `dispatcher`. Die
+ * Mock-Klasse zeichnet nur die uebergebenen `options` auf; `fetch` delegiert
+ * ZUR LAUFZEIT (Pfeilfunktion, nicht beim Laden aufgeloest) an
+ * `globalThis.fetch`, damit alle bestehenden `vi.stubGlobal('fetch', …)`-
+ * Tests wortgleich gruen bleiben.
+ */
+vi.mock('undici', () => ({
+  Agent: class Agent {
+    constructor(public readonly options: unknown) {}
+  },
+  fetch: (...args: unknown[]) => (globalThis.fetch as any)(...args),
+}));
+
+import { Agent } from 'undici';
 import {
   IconDiscoveryService,
   isPublicHttpUrl,
@@ -203,3 +221,69 @@ describe('IconDiscoveryService.discoverFavoriteIconUrl (unchanged behaviour)', (
     expect(typeof result).toBe('string');
   });
 });
+
+describe('IconDiscoveryService — Dispatcher (260917-jdd)', () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+    vi.unstubAllGlobals();
+  });
+
+  it('discoverFavoriteIconUrl uebergibt den tolerante-TLS-Agent als dispatcher und redirect: manual', async () => {
+    const html = '<html><head><link rel="icon" href="https://ctl.de/fav.png" /></head></html>';
+    const fetchSpy = vi.fn().mockResolvedValue({
+      ok: true,
+      status: 200,
+      headers: {
+        get: (n: string) =>
+          n.toLowerCase() === 'content-type' ? 'text/html; charset=utf-8' : null,
+      },
+      text: async () => html,
+    });
+    vi.stubGlobal('fetch', fetchSpy);
+
+    const service = new IconDiscoveryService();
+    await service.discoverFavoriteIconUrl('http://8.8.8.8');
+
+    const init = fetchSpy.mock.calls[0][1];
+    expect(init.dispatcher).toBeInstanceOf(Agent);
+    expect(init.dispatcher.options).toEqual({ connect: { rejectUnauthorized: false } });
+    expect(init.redirect).toBe('manual');
+  });
+
+  it('fetchIconBytes uebergibt denselben tolerante-TLS-Agent als dispatcher und redirect: manual', async () => {
+    const fetchSpy = vi.fn().mockResolvedValue(mockResponse({ contentType: 'image/png' }));
+    vi.stubGlobal('fetch', fetchSpy);
+
+    const service = new IconDiscoveryService();
+    await service.fetchIconBytes('http://8.8.8.8/favicon.ico');
+
+    const init = fetchSpy.mock.calls[0][1];
+    expect(init.dispatcher).toBeInstanceOf(Agent);
+    expect(init.dispatcher.options).toEqual({ connect: { rejectUnauthorized: false } });
+    expect(init.redirect).toBe('manual');
+  });
+
+  it('Discovery und fetchIconBytes teilen DENSELBEN Agent (Modul-Singleton)', async () => {
+    const html = '<html><head></head></html>';
+    const fetchSpy = vi
+      .fn()
+      .mockResolvedValueOnce({
+        ok: true,
+        status: 200,
+        headers: {
+          get: (n: string) =>
+            n.toLowerCase() === 'content-type' ? 'text/html; charset=utf-8' : null,
+        },
+        text: async () => html,
+      })
+      .mockResolvedValueOnce(mockResponse({ contentType: 'image/png' }));
+    vi.stubGlobal('fetch', fetchSpy);
+
+    const service = new IconDiscoveryService();
+    await service.discoverFavoriteIconUrl('http://8.8.8.8');
+    await service.fetchIconBytes('http://8.8.8.8/favicon.ico');
+
+    const calls = fetchSpy.mock.calls;
+    expect(calls[0][1].dispatcher).toBe(calls[1][1].dispatcher);
+  });
+});
diff --git a/apps/api/src/favorites/icon-discovery.service.ts b/apps/api/src/favorites/icon-discovery.service.ts
index 33fed34..90de12a 100644
--- a/apps/api/src/favorites/icon-discovery.service.ts
+++ b/apps/api/src/favorites/icon-discovery.service.ts
@@ -1,6 +1,7 @@
 import { Injectable } from '@nestjs/common';
 import { lookup } from 'dns/promises';
 import { isIP } from 'net';
+import { Agent, fetch as undiciFetch, type Response as UndiciResponse } from 'undici';
 
 /**
  * Server-side favicon / icon discovery with SSRF protection (T-08-05).
@@ -12,6 +13,9 @@ import { isIP } from 'net';
  * - 4000 ms AbortController timeout per request
  * - 200 000 character HTML cap to prevent memory exhaustion (T-08-09)
  * - Blocked hostnames: localhost, .local, 0.0.0.0
+ * - 260917-jdd: Zertifikatsfehler des Zielhosts werden toleriert (siehe
+ *   LENIENT_TLS_AGENT unten) — DNS-Pruefung, Redirect-Limit, Timeout und
+ *   Groessendeckel bleiben davon unberuehrt.
  */
 
 const FALLBACK_ICON_PATH = '/favicon.ico';
@@ -21,6 +25,27 @@ const MAX_REDIRECTS = 2;
 const MAX_HTML_CHARS = 200000;
 const MAX_ICON_BYTES = 1_000_000;
 
+/**
+ * 260917-jdd — Ziel ist ein Bildchen, kein Geheimnis: selbstsignierte,
+ * abgelaufene oder falsch benannte Zertifikate sollen das Symbol eines
+ * Favoriten nicht verhindern. Dieser Dispatcher gilt AUSSCHLIESSLICH fuer
+ * die beiden Aufrufe in dieser Datei (Dispatcher pro Aufruf, keine
+ * prozessweite Abschaltung der Zertifikatspruefung — insbesondere NICHT
+ * ueber die Node-Umgebungsvariable, die mit NODE_TLS_ beginnt).
+ *
+ * Der Dispatcher wirkt nur zusammen mit undicis EIGENEM `fetch` — Nodes
+ * globales `fetch` ignoriert einen Agent aus dem npm-Paket (andere Klasse,
+ * Node 24 buendelt intern undici 7.25.0). Gemessen 2026-09-17 gegen
+ * self-signed.badssl.com: `undiciFetch(url, { dispatcher: new Agent(...) })`
+ * -> Status 200; `globalThis.fetch` derselben URL -> DEPTH_ZERO_SELF_SIGNED_CERT.
+ * Deshalb der Modulimport oben statt des globalen `fetch`.
+ *
+ * DNS-Pruefung (isPublicHttpUrl), Redirect-Limit (MAX_REDIRECTS), Timeout
+ * und Groessendeckel (MAX_ICON_BYTES/MAX_HTML_CHARS) bleiben davon
+ * unberuehrt (T-JDD-01).
+ */
+const LENIENT_TLS_AGENT = new Agent({ connect: { rejectUnauthorized: false } });
+
 type FetchHtmlResult = {
   html: string;
   finalUrl: string;
@@ -243,7 +268,7 @@ function extractIconFromHtml(html: string, baseUrl: string): string | null {
 async function fetchWithRedirectGuard(
   pageUrl: URL,
   options: { accept: string; timeoutMs: number; userAgent?: string },
-): Promise<{ response: Response; finalUrl: URL } | null> {
+): Promise<{ response: UndiciResponse; finalUrl: URL } | null> {
   let currentUrl = pageUrl;
 
   for (let redirectCount = 0; redirectCount <= MAX_REDIRECTS; redirectCount++) {
@@ -255,7 +280,8 @@ async function fetchWithRedirectGuard(
     const timeout = setTimeout(() => controller.abort(), options.timeoutMs);
 
     try {
-      const response = await fetch(currentUrl.toString(), {
+      const response = await undiciFetch(currentUrl.toString(), {
+        dispatcher: LENIENT_TLS_AGENT, // 260917-jdd: siehe Kommentar an der Konstante
         redirect: 'manual', // SSRF: follow manually so each hop is re-validated
         signal: controller.signal,
         headers: {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f838462..d81eb9f 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -82,7 +82,7 @@ importers:
         version: 7.0.1
       ews-javascript-api:
         specifier: 0.15.3
-        version: 0.15.3
+        version: 0.15.3(undici@7.28.0)
       fast-xml-parser:
         specifier: ^5.10.1
         version: 5.10.1
@@ -128,6 +128,9 @@ importers:
       tsdav:
         specifier: 2.2.2
         version: 2.2.2
+      undici:
+        specifier: 7.28.0
+        version: 7.28.0
       xlsx:
         specifier: ^0.18.5
         version: 0.18.5
@@ -6190,11 +6193,11 @@ snapshots:
     optionalDependencies:
       extend: 3.0.2
 
-  '@ewsjs/xhr@3.1.3':
+  '@ewsjs/xhr@3.1.3(undici@7.28.0)':
     dependencies:
       '@ewsjs/ntlm-client': 3.0.1
       axios: 1.18.1
-      http-cookie-agent: 5.0.4(tough-cookie@4.1.4)
+      http-cookie-agent: 5.0.4(tough-cookie@4.1.4)(undici@7.28.0)
       tough-cookie: 4.1.4
     transitivePeerDependencies:
       - deasync
@@ -8511,10 +8514,10 @@ snapshots:
 
   events@3.3.0: {}
 
-  ews-javascript-api@0.15.3:
+  ews-javascript-api@0.15.3(undici@7.28.0):
     dependencies:
       '@azure/msal-node': 2.16.3
-      '@ewsjs/xhr': 3.1.3
+      '@ewsjs/xhr': 3.1.3(undici@7.28.0)
       '@xmldom/xmldom': 0.8.13
       base64-js: 1.5.1
       moment: 2.30.1
@@ -8987,10 +8990,12 @@ snapshots:
       entities: 4.5.0
     optional: true
 
-  http-cookie-agent@5.0.4(tough-cookie@4.1.4):
+  http-cookie-agent@5.0.4(tough-cookie@4.1.4)(undici@7.28.0):
     dependencies:
       agent-base: 7.1.4
       tough-cookie: 4.1.4
+    optionalDependencies:
+      undici: 7.28.0
 
   http-errors@2.0.1:
     dependencies: