Having spent some time in the anti-abuse and Trust & Safety space, I always take these vendor reports with a massive grain of salt. It’s a classic case of comparing apples to vendor-marketing oranges. A headline screaming about an 84% miss rate sounds like a systemic collapse until you look at the radically different constraint envelopes a global default like GSB and a specialized enterprise vendor operate under.

The biggest factor here is the false-positive cliff. Google Safe Browsing is the default safety net for billions of clients across Chrome, Safari, and Firefox. If GSB’s false-positive rate ticks up by even a fraction of a percent, they end up accidentally nuking legitimate small businesses, SaaS platforms, or municipal portals off the internet. Because of that massive blast radius, GSB fundamentally has to be deeply conservative. A boutique security vendor, on the other hand, can afford to be highly aggressive because an over-block in a corporate environment just results in a routine IT support ticket.

You also have to factor in the ephemeral nature of modern phishing infrastructure and basic selection bias. Threat actors heavily rely on automated DGAs and compromised hosts where the time-to-live for a payload is measured in hours, if not minutes. If a specialized vendor detects a zero-day phishing link at 10:00 AM, and GSB hasn't confidently propagated a global block to billions of edge clients by 10:15 AM, the vendor scores it as a "miss." Add in the fact that vendors naturally test against the specific subset of threats their proprietary engines are tuned to find, and that 84% number starts to make a lot more sense as a top-of-funnel marketing metric rather than a scientific baseline.

None of this is to say GSB is perfect right now. It has absolutely struggled to keep up with the recent explosion of automated, highly targeted spear-phishing and MFA-bypass proxy kits. But we should read this report for what it really is: a smart marketing push by a security vendor trying to sell a product, not a sign that the internet's baseline immune system is totally broken.

> We also ran the full dataset of 263 URLs (254 phishing, 9 confirmed legitimate) through Muninn's automatic scan. This is the scan that runs on every page you visit without any action on your part. On its own, the automatic scan correctly identified 238 of the 254 phishing sites and only incorrectly flagged 6 legitimate pages. [...] The tradeoff is that it flagged all 9 of the legitimate sites in our dataset as suspicious, ...

Am I missing something or is that a 66%/100% False Positive Rate on legitimate Sites?

If GSB would have that ratio, it would be absolute unusable.. So comparing these two is absolutely wrong...

> I always take these vendor reports with a massive grain of salt. It’s a classic case of comparing apples to vendor-marketing oranges. A headline screaming about an 84% miss rate sounds like a systemic collapse until...

I've seen this before in the ip blocklist space... if you're layering up firewall rules, you're bound to see the higher priority layers more often.

That doesn't mean the other layers suck, security isn't always an A or B situation...

On the other hand, I don't know how I feel about how GSB is implemented... you're telling google every website you go to, but chances are the site already has google analytics or SSO...

> I always take these vendor reports with a massive grain of salt.

Yeah. "Here's a blog post with some casually collected numbers about our product [...] It turns out that it's great!" is sorta boring.

But couple that with a headline framed as "Google [...] Bad" and straight to the top of the HN front page it goes!

These are fair points and I agree with a lot of them. GSB operates at a scale we don't, and the conservatism that comes with being the default for billions of users is a real constraint. The post tries to acknowledge that ("the takeaway from all of this is not that Google Safe Browsing is bad") and we're upfront about the timing caveat since these were checked at time of scan.

Where I'd push back is on what this means for the average person. Most people have no protection against phishing beyond what their email provider and browser give them. If that protection is fundamentally reactive, catching threats hours or days after they go live, that's a real limitation worth talking about honestly. The 84% number isn't meant to say GSB is broken. It's meant to say there's a gap, and that gap has consequences for real users regardless of the engineering reasons behind it.

On the marketing angle, we aren't currently selling anything. The extension is free and so is submitting URLs for verification. We recognize it would be disingenuous to say we never will, but at the very least the data and the ability to check URLs (similar to PhishTank before they closed registration) will always be free. The dataset is also sourced from public threat intelligence feeds, not a curated set designed to make our tool look good. We think publishing findings like this is valuable even if you set aside everything about our tools.