Google Safe Browsing: Prevent and Fix

One upstream blocklist (Google Safe Browsing) feeds Chrome, Brave, Safari, Firefox, and Edge. A flag there blocks the site in every browser at once. It is a classification of the public surface, not a hack — do not start by debugging code.

Quick check: is a site flagged?

# Replace the domain. Check apex AND www — they are scored separately.
curl -s "https://transparencyreport.google.com/transparencyreport/api/v3/safebrowsing/status?site=example.com"

Response is )]}' followed by [["sb.ssr", STATUS, bool, bool, bool, bool, bool, timestamp_ms, "site"]]:

• STATUS 1 + all false = clean.
• STATUS 2 + any true = flagged. The browser interstitial text tells the category: "trick you into revealing passwords" = deceptive/social-engineering; "install dangerous programs" = malware.

Human-readable version: https://transparencyreport.google.com/safe-browsing/search?url=example.com

Prevention checklist (every new public web project)

1. No third-party trademarks in the domain. youtube-x.com, paypal-tool.io = brand + login form = automated phishing flag, and a trademark complaint risk. Use subdomains of a domain you own (tool.yourname.com).
2. Crawlers must never land on a credential form. Root URL for anonymous visitors goes to a neutral landing page: no inputs, clear owner ("Operated by X"), explicit "Not affiliated with [brand]" if the product touches one. Login lives behind a link.
3. Search Console on day one, every domain. Add a Domain property, drop the TXT record at the registrar. It is the only channel where Google warns you BEFORE users see red screens, and the only door to request a review after a flag.
4. Public URL = public site. "Internal tool" means nothing to a classifier. Kill stray waitlist/signup forms on tools that are actually invite-only; young domain + email-collection forms looks like a harvesting kit.
5. Verify like a stranger. curl -sL https://the-domain/ and check: lands on neutral content, no password field, no third-party brand in title/headings.

Diagnosis workflow (site already flagged)

1. Run the Quick check on apex and www. Confirm flag + category.
2. Fetch the site anonymously (curl -sL), see exactly what Googlebot sees. Look for: brand names in domain/title/headings, immediate redirect to a credential form, public email-collection forms, young domain age (whois).
3. Git history is usually a red herring — the trigger is a re-crawl/reclassification or a user report, not a recent commit. Skim it only to rule out injected scripts or a compromised dependency.
4. If user uploads or third-party content are hosted on the domain, check whether a specific uploaded file/page tripped the flag (Search Console lists sample URLs).

Recovery

1. Fix the public surface first (checklist above) and deploy. Reviews against an unchanged phishy surface get denied and repeat offenses take longer.
2. Verify the domain in Search Console (DNS TXT at the registrar, propagates in minutes).
3. Search Console > Security Issues > Request Review. One or two factual sentences: what the site is, who uses it, what was changed.
4. Typical turnaround 1-3 days. Validate: re-run the Quick check until it returns STATUS 1, then confirm in a browser.
5. If the domain itself contains someone else's trademark, treat the cleared flag as temporary — it stays re-flag-prone. The durable fix is moving to a neutral domain.

Worked example

example-brand-tool.com: internal team tool, domain contained a well-known brand name, anonymous visitors were redirected straight to a branded email+password form, plus a public waitlist form. Flagged as deceptive site; blocked in Brave/Chrome. Fix: deleted waitlist page, added neutral /welcome landing (ownership + non-affiliation notice), de-branded all logged-out pages, then Search Console review. Code was never the problem.