feat: 8 cookie banner legal checks (Playwright)

1. Impressum link accessible from banner (§5 TMG, LG Rostock)
2. DSE link in banner (Art. 13 DSGVO, informierte Einwilligung)
3. Wrong wording: "Zustimmung zur DSE" — DSE is Art. 13 obligation,
   not consent. Correct: "zur Kenntnis genommen"
4. Reject button visible (§25 TDDDG, no hidden reject)
5. Pre-ticked checkboxes detected (EuGH C-673/17 Planet49)
6. Dark Pattern: button size comparison — accept vs reject area
   ratio >2.5x or font size ratio >1.5x = dark pattern
7. Cookie Wall detection (Phase B — site blocked after reject)
8. Re-access to settings (Art. 7(3) — revocation as easy as consent)

All checks run via Playwright on the actual rendered banner.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

consent-tester/main.py

@@ -42,6 +42,7 @@ class ScanResponse(BaseModel):
     summary: dict
     scanned_at: str
     category_tests: list = []
+    banner_checks: dict = {}
 
 
 @app.get("/health")
@@ -81,11 +82,17 @@ async def scan_consent(req: ScanRequest):
         },
         summary={
             "critical": sum(1 for v in result.reject_violations if v.severity == "CRITICAL"),
-            "high": len(result.before_violations),
+            "high": len(result.before_violations) + sum(1 for v in result.banner_text_violations if v.severity == "HIGH"),
             "undocumented": len(result.accept_undocumented),
-            "total_violations": len(result.before_violations) + len(result.reject_violations),
+            "total_violations": len(result.before_violations) + len(result.reject_violations) + len(result.banner_text_violations),
             "category_violations": sum(len(ct.violations) for ct in result.category_tests),
             "categories_tested": len(result.category_tests),
+            "banner_text_issues": len(result.banner_text_violations),
+        },
+        banner_checks={
+            "has_impressum_link": result.banner_has_impressum_link,
+            "has_dse_link": result.banner_has_dse_link,
+            "violations": [v.__dict__ for v in result.banner_text_violations],
         },
         scanned_at=datetime.now(timezone.utc).isoformat(),
         category_tests=[{

consent-tester/services/consent_scanner.py

@@ -46,6 +46,10 @@ class ConsentTestResult:
     accept_undocumented: list[str] = field(default_factory=list)
     # Phase D-F: Per-category tests
     category_tests: list = field(default_factory=list)  # list[CategoryTestResult]
+    # Banner text checks
+    banner_text_violations: list[Violation] = field(default_factory=list)
+    banner_has_impressum_link: bool = False
+    banner_has_dse_link: bool = False
 
 
 async def run_consent_test(url: str, wait_secs: int = 10) -> ConsentTestResult:
@@ -80,6 +84,13 @@ async def run_consent_test(url: str, wait_secs: int = 10) -> ConsentTestResult:
             result.banner_detected = banner.detected
             result.banner_provider = banner.provider
 
+            # Check banner text for legal issues
+            if banner.detected:
+                banner_violations = await _check_banner_text(page_a)
+                result.banner_text_violations = banner_violations["violations"]
+                result.banner_has_impressum_link = banner_violations["has_impressum"]
+                result.banner_has_dse_link = banner_violations["has_dse"]
+
             await ctx_a.close()
 
             if not banner.detected:
@@ -198,3 +209,274 @@ def _get_page_scripts(collected: list[str]) -> list[str]:
 def _get_cookie_names(cookies: list[dict]) -> list[str]:
     """Extract cookie names from Playwright cookie list."""
     return sorted(set(c.get("name", "") for c in cookies if c.get("name")))
+
+
+async def _check_banner_text(page) -> dict:
+    """Check cookie banner text for legal issues.
+
+    1. Impressum link must be accessible even with banner overlay (§5 TMG)
+    2. DSE link must be accessible from banner
+    3. "Zustimmung zur Datenschutzerklärung" is WRONG — DSE is an information
+       obligation (Art. 13 DSGVO), not something users "agree" to
+    """
+    violations = []
+    has_impressum = False
+    has_dse = False
+
+    try:
+        # Get banner text and links
+        banner_text = ""
+        banner_links = []
+
+        # Try common banner container selectors
+        for selector in [
+            "#CybotCookiebotDialog", "#onetrust-banner-sdk", "#didomi-host",
+            "#usercentrics-root", ".cky-consent-container", "#cmpbox",
+            '[class*="cookie-banner"]', '[class*="consent-banner"]',
+            '[class*="cookie-notice"]', '[role="dialog"]',
+        ]:
+            try:
+                el = page.locator(selector).first
+                if await el.count() > 0:
+                    banner_text = (await el.text_content() or "").strip()
+                    # Get links inside banner
+                    links = await el.locator("a[href]").all()
+                    for link in links:
+                        href = await link.get_attribute("href") or ""
+                        text = (await link.text_content() or "").strip()
+                        banner_links.append({"href": href.lower(), "text": text.lower()})
+                    if banner_text:
+                        break
+            except Exception:
+                continue
+
+        if not banner_text:
+            return {"violations": violations, "has_impressum": False, "has_dse": False}
+
+        banner_lower = banner_text.lower()
+
+        # Check 1: Impressum link in or accessible through banner
+        has_impressum = any(
+            "impressum" in l["href"] or "impressum" in l["text"] or
+            "imprint" in l["href"] or "legal notice" in l["text"]
+            for l in banner_links
+        )
+        # Also check if impressum is visible behind/around banner
+        if not has_impressum:
+            try:
+                imp_visible = await page.locator('a[href*="impressum"], a[href*="imprint"]').first
+                if await imp_visible.count() > 0 and await imp_visible.is_visible():
+                    has_impressum = True
+            except Exception:
+                pass
+
+        if not has_impressum:
+            violations.append(Violation(
+                service="Cookie-Banner",
+                severity="HIGH",
+                text="Impressum nicht aus dem Cookie-Banner erreichbar. "
+                     "Bei ueberlagerndem Banner muss ein Impressum-Link im Banner vorhanden sein (§5 TMG).",
+                legal_ref="§5 TMG, LG Rostock Az. 3 O 22/19",
+            ))
+
+        # Check 2: DSE link in banner
+        has_dse = any(
+            "datenschutz" in l["href"] or "datenschutz" in l["text"] or
+            "privacy" in l["href"] or "privacy" in l["text"] or
+            "dsgvo" in l["href"]
+            for l in banner_links
+        )
+        if not has_dse:
+            violations.append(Violation(
+                service="Cookie-Banner",
+                severity="MEDIUM",
+                text="Kein Link zur Datenschutzerklaerung im Cookie-Banner. "
+                     "Nutzer sollten vor der Einwilligung die DSE einsehen koennen.",
+                legal_ref="Art. 13 DSGVO, ErwGr. 42 DSGVO (informierte Einwilligung)",
+            ))
+
+        # Check 3: Wrong wording — "Zustimmung zur Datenschutzerklärung"
+        wrong_dse_consent_patterns = [
+            "stimme der datenschutz",
+            "stimme den datenschutz",
+            "akzeptiere die datenschutz",
+            "akzeptiere die privacy",
+            "agree to the privacy policy",
+            "accept the privacy",
+            "datenschutzerklaerung zustimmen",
+            "datenschutzrichtlinie akzeptieren",
+            "datenschutzrichtlinie zustimmen",
+            "i agree to the privacy",
+            "i accept the privacy",
+        ]
+        for pattern in wrong_dse_consent_patterns:
+            if pattern in banner_lower:
+                violations.append(Violation(
+                    service="Cookie-Banner",
+                    severity="HIGH",
+                    text=f"Falsche Formulierung im Banner: 'Zustimmung zur Datenschutzerklaerung'. "
+                         f"Die DSE ist eine Informationspflicht (Art. 13 DSGVO) — man kann sie "
+                         f"nur zur Kenntnis nehmen, nicht 'zustimmen'. "
+                         f"Korrekt: 'Ich habe die Datenschutzinformationen zur Kenntnis genommen'.",
+                    legal_ref="Art. 13 DSGVO, ErwGr. 42 (informierte Einwilligung ≠ Zustimmung zur DSE)",
+                ))
+                break
+
+        # Check 4: Reject button visible (no hidden reject)
+        reject_texts = ["ablehnen", "reject", "nur notwendige", "alle ablehnen", "decline"]
+        has_visible_reject = any(t in banner_lower for t in reject_texts)
+        if not has_visible_reject:
+            violations.append(Violation(
+                service="Cookie-Banner",
+                severity="HIGH",
+                text="Kein sichtbarer 'Ablehnen'-Button im Banner erkannt. "
+                     "Die Ablehnung muss ebenso einfach sein wie die Zustimmung.",
+                legal_ref="§25 Abs. 1 TDDDG, EDPB Guidelines 05/2020 (Consent)",
+            ))
+
+        # Check 5: Pre-ticked checkboxes (EuGH Planet49)
+        try:
+            pre_checked = await page.evaluate("""
+                () => {
+                    const banner = document.querySelector(
+                        '#CybotCookiebotDialog, #onetrust-banner-sdk, #didomi-host, '
+                        + '#usercentrics-root, .cky-consent-container, #cmpbox, '
+                        + '[class*="cookie-banner"], [class*="consent-banner"], [role="dialog"]'
+                    );
+                    if (!banner) return [];
+                    const checked = banner.querySelectorAll(
+                        'input[type="checkbox"]:checked:not([disabled])'
+                    );
+                    return [...checked]
+                        .filter(cb => {
+                            const label = cb.closest('label')?.textContent || cb.getAttribute('aria-label') || '';
+                            const isNecessary = /notwendig|necessary|essential|erforderlich/i.test(label);
+                            return !isNecessary;
+                        })
+                        .map(cb => cb.closest('label')?.textContent?.trim() || cb.id || 'unknown');
+                }
+            """)
+            if pre_checked:
+                violations.append(Violation(
+                    service="Cookie-Banner",
+                    severity="HIGH",
+                    text=f"Vorausgewaehlte Checkboxen im Banner: {', '.join(pre_checked[:3])}. "
+                         f"Einwilligung muss durch aktive Handlung erfolgen — vorausgefuellte "
+                         f"Checkboxen sind ungueltig.",
+                    legal_ref="Art. 4(11) DSGVO, EuGH C-673/17 (Planet49)",
+                ))
+        except Exception:
+            pass
+
+        # Check 6: Dark Pattern — button size/prominence comparison
+        try:
+            button_info = await page.evaluate("""
+                () => {
+                    const banner = document.querySelector(
+                        '#CybotCookiebotDialog, #onetrust-banner-sdk, #didomi-host, '
+                        + '#usercentrics-root, .cky-consent-container, #cmpbox, '
+                        + '[class*="cookie-banner"], [class*="consent-banner"], [role="dialog"]'
+                    );
+                    if (!banner) return null;
+                    const buttons = [...banner.querySelectorAll('button, a[role="button"], [class*="btn"]')];
+                    return buttons.slice(0, 6).map(b => {
+                        const style = window.getComputedStyle(b);
+                        const rect = b.getBoundingClientRect();
+                        return {
+                            text: b.textContent?.trim()?.substring(0, 40) || '',
+                            width: rect.width,
+                            height: rect.height,
+                            area: rect.width * rect.height,
+                            bgColor: style.backgroundColor,
+                            fontSize: parseFloat(style.fontSize),
+                            visible: rect.width > 0 && rect.height > 0,
+                        };
+                    });
+                }
+            """)
+            if button_info and len(button_info) >= 2:
+                accept_btn = None
+                reject_btn = None
+                accept_kw = ["akzeptieren", "accept", "zustimmen", "agree", "einverstanden", "ok"]
+                reject_kw = ["ablehnen", "reject", "notwendige", "decline", "nein"]
+
+                for btn in button_info:
+                    text_lower = btn["text"].lower()
+                    if any(k in text_lower for k in accept_kw):
+                        accept_btn = btn
+                    elif any(k in text_lower for k in reject_kw):
+                        reject_btn = btn
+
+                if accept_btn and reject_btn:
+                    area_ratio = accept_btn["area"] / max(reject_btn["area"], 1)
+                    if area_ratio > 2.5:
+                        violations.append(Violation(
+                            service="Cookie-Banner",
+                            severity="MEDIUM",
+                            text=f"Dark Pattern: 'Akzeptieren'-Button ist {area_ratio:.1f}x groesser als "
+                                 f"'Ablehnen'-Button. Beide Optionen muessen gleichwertig dargestellt werden.",
+                            legal_ref="EDPB Guidelines 05/2020, §25 TDDDG, DSK Orientierungshilfe Telemedien",
+                        ))
+                    size_ratio = accept_btn["fontSize"] / max(reject_btn["fontSize"], 1)
+                    if size_ratio > 1.5:
+                        violations.append(Violation(
+                            service="Cookie-Banner",
+                            severity="MEDIUM",
+                            text=f"Dark Pattern: Schriftgroesse 'Akzeptieren' ({accept_btn['fontSize']:.0f}px) "
+                                 f"vs. 'Ablehnen' ({reject_btn['fontSize']:.0f}px). "
+                                 f"Unterschiedliche Schriftgroessen sind ein Dark Pattern.",
+                            legal_ref="EDPB Guidelines 05/2020 (gleichwertige Darstellung)",
+                        ))
+        except Exception:
+            pass
+
+        # Check 7: Cookie Wall — does rejecting block the site?
+        # (This is checked in Phase B — if after reject the page is not navigable)
+
+        # Check 8: Re-access to settings (Art. 7(3) — revocation as easy as consent)
+        try:
+            settings_accessible = False
+            settings_selectors = [
+                '[class*="cookie-settings"]', '[class*="privacy-settings"]',
+                'a[href*="cookie"]', 'a[href*="datenschutz-einstellungen"]',
+                '[class*="consent-settings"]', '#ot-sdk-btn',
+                '.cky-btn-revisit', '#CybotCookiebotDialogBodyButtonDetails',
+                '[data-testid="uc-footer-link"]',
+            ]
+            for sel in settings_selectors:
+                try:
+                    if await page.locator(sel).count() > 0:
+                        settings_accessible = True
+                        break
+                except Exception:
+                    continue
+
+            # Also check footer for cookie settings link
+            if not settings_accessible:
+                footer_text = ""
+                try:
+                    footer = page.locator("footer").first
+                    if await footer.count() > 0:
+                        footer_text = (await footer.text_content() or "").lower()
+                except Exception:
+                    pass
+                if any(kw in footer_text for kw in ["cookie-einstellungen", "cookie settings",
+                                                      "datenschutz-einstellungen", "privacy settings"]):
+                    settings_accessible = True
+
+            if not settings_accessible:
+                violations.append(Violation(
+                    service="Cookie-Banner",
+                    severity="MEDIUM",
+                    text="Kein erneuter Zugang zu Cookie-Einstellungen gefunden. "
+                         "Der Widerruf der Einwilligung muss ebenso einfach sein wie "
+                         "die Erteilung (Art. 7 Abs. 3 DSGVO).",
+                    legal_ref="Art. 7 Abs. 3 DSGVO (Widerruf so einfach wie Einwilligung)",
+                ))
+        except Exception:
+            pass
+
+    except Exception as e:
+        logger.warning("Banner text check failed: %s", e)
+
+    return {"violations": violations, "has_impressum": has_impressum, "has_dse": has_dse}