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Comment by ZeroCool2u | Hacker News Reader

This is an elegant attack that effectively compromises all Titan M chips. They were even able to dump all securely stored private cryptographic keys, which Google acknowledges in the disclosure timeline.

Even still though, the award Google initially gave was only $10k USD(!). They finally bumped it to $75k USD after complaint and review, but Google's bug bounty program claims up to $1 Million USD.

If fully compromising Google's own security chip to dump all private keys isn't worth the full $1 Million bounty, I honestly don't know what is.

Really, what would, in the mind of those on the internal committee, constitute justification for the $1 Million bounty?

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From my point of view, the fact that the exploit required either to run as root on a rooted device (or alternatively direct access to an internal serial bus) is enough to justify not paying at the top level.

These things should probably be more transparent, but I would assume the $1M level would be for exploits that could be deployed on a fresh-from-the-box device with no rooting/mods.

is isb access an issue? your phone could get stolen

Sure; but it's a sliding scale, right? Zero-click network exploits are more severe than interactive exploits are more severe than those which require physical access etc.

Quoting a random article from when this was initially announced:

> Google says that if researchers manage to find "a full chain remote code execution exploit with persistence" that also compromises data protected by Titan M, they are willing to pay up to $1 million to the bug hunter who finds it.

So a compromise that doesn't require physical access or root, presumably.

Cue also the inevitable discussion that bug bounties are too low.

> Really, what would, in the mind of those on the internal committee, constitute justification for the $1 Million bounty?

Probably something that doesn't require physical access to a key for longer time to extract the keys?

Remote 0-day onto all google internal infra?

thats literally worth billions, and could be sold to many governments.

If thr right people don't buy these zero-days, yhe wrong people will.

Billions? couldn’t a government just get a person affiliated with them hired by google?

Most Google employees do not have direct access to all infra.

Google bug bounty program is a sham. When I tried to report critical vulnerability in their authentication system, they told it's a 'feature' and threatened to sue if I disclose.

Then fixed it in two and a half years, and wrote an article on how complicated bug they just found and how proud and secure they are with their pentesters.

Do you have a link?

It was looong time ago (2011). You could use app specific password to change master password and disable 2FA, with a script.

Funny thing. I had to discover this way myself when I lost my phone with Authenticator App. I took my mail client password and discovered that with some header magic I was able to hijack my own account. I couldn't believed it. So I created another account, protected with 2FA and did same thing. Got gaslighted by Google bug bounty team and decided it's not worth it.

You have inadvertently discovered the value of pentesters which is making handling security issues a win for the the management.

On what grounds could they sue you if it was truly considered a "feature", and they used that exact terminology in their response?

This article [1] includes a quote describing a specific vulnerability that would pay the $1 million.

> "We are introducing a top prize of $1 million for a full chain remote code execution exploit with persistence which compromises the Titan M secure element on Pixel devices. Additionally, we will be launching a specific program offering a 50% bonus for exploits found on specific developer preview versions of Android, meaning our top prize is now $1.5 million," Jessica Lin of the Android security team said.

> The Titan M bounty applies to the Google phones that have the chip, which include the Pixel 3 and 3 XL, 3a and 3a XL, and 4.

[1] https://duo.com/decipher/hack-the-titan-m-get-usd1-million

For 2018 chip and for a company like Google, the decision to go with C despite their all knowledge oN C/C++ memory issues (hello Chrome) is a bit sad.

I would imagine it wasn't a hard decision - they likely needed to build something in an environment where they are already paying 40-80k C++ developers, and I would guess something like 1-10k Rust developers, who are scattered around various teams and may not want to hop on a new team right now. Also it was released to the consumer market in 2018, so probably built in 2016-17. Rust and other memory-safe systems programming alternatives didn't have nearly the same uptake back then - so maybe 1-2k would be a safer bet. Not to mention, Rust didn't get tier-1 ARM support until 2021 - and even then, that's only when running on linux, which the Titan M chip is most likely not running.

I think the $1M is probably reserved to something that would tank Google stock imo, but maybe I'm cynical

Nah, you're not cynical enough. My cynical take is there is nothing they would ever pay $1M for. "Up to" is a marketing term to get people to think that if they work hard enough, they might qualify for this mythical unicorn bounty, but at the end of the day they just get peanuts.

"You might win this car!"

Really sign me up!

First, we'll need you to fill out this form with some basic information:

  --First, Middle, Last Name
  --Phone number, email address, social contacts
  --Mother's Maiden Name
  --First concert you attended
  --Name of the street you grew up on
  --Name of your best friend
  --Name of your first pet
  --Make/Model of your first car

i would imagine higher bounty would be for extracting device keys. from my reading this exploit would not allow you to extract the key needed to unlock a powered off device. im no security expert so please correct me if im wrong

>2022-06-20: Quarkslab sent Google a new exploit that demonstrates code execution on the chip and exfiltration of encryption keys from it. A detailed description of the exploitation technique, the exploit's source code, and a video showing its use to exfiltrate a StrongBox-protected AES key were provided.

This sounds close enough to me, but perhaps there's some subtle nuance between device keys and other keys in the chip.

> perhaps there's some subtle nuance between device keys and other keys in the chip.

Thats what im wondering too. particularly this line from mitigations section from the report

>> However, we do want to point out an interesting feature that would have made the StrongBox key blob leak impossible. Indeed, an application can create a key that is authentication-bound, specifying setUserAuthenticationRequired(true) when building it with KeyGenParameterSpec. This way, users need to authenticate before using the key and the key blob is encrypted a second time using a special key derived from the user password that we do not have.

so unless your phone doesnt have a password i dont see how they can retrieve device keys

Yeah, okay I definitely missed that part. Makes more sense. Still, the bounty seems shockingly low. They probably could've gotten a lot more for it on the open market.

yeah i think its a noteworthy attack and defn worth more than 10K. also google should be more open about how bug bounties are evaluated

Those committee's just lost contact to the real world. Ridiculous

I guess there's someone who orders the marketing department to say "1 million", while telling the operational side "10k", because his bonus rides on it.

That's not how it works. Bug bounties work like this.

Somebody sets up a bounty program and defines a framework for deciding how much to pay out. Security is complicated as hell and you cannot possibly devise a framework that accounts for all possible things so this framework is necessarily brittle. For example, you might reasonably decide that the highest payouts require very minimal attacker capabilities (fully remote unauthenticated attacks being the top payouts). This makes sense since those are the easiest attacks to mount.

So now a bounty comes in. It goes to a triage person or, at best, a small group. They refer to the framework. Your bug doesn't really match any of the categories but it kind of looks like this thing over here so it gets bucketed as such. Maybe there is some discussion. Ultimately, the rules say "max payout requires unauthenticated remote attacks" so the payout ends up lower, even if the attack is exciting. Maybe somebody managing the system takes a note to update the framework and policy moving forward. The community then rages about how this bug is actually a big deal and deserves a lot of reward.

In my experience, the people managing these programs get rewarded based on the amount they pay out going up, not down. But you need a payment framework otherwise each bug is paid out on somebody's whim (and trust me, the security researchers will complain to high heaven if they perceive inconsistency in bounty sizes). So you end up with novel bug structures that aren't handled well by the framework and get treated weirdly.

I'm still surprised by the $10k payout given the disclosure timeline. For example they indicate that on 2022-05-04 there was a "conference call between Quarkslab engineers, Google Android Security Team members, and a Titan engineering team member." Since there were both Android security team members and a Titan engineer in the phone call there were clearly engineers in the loop who understood the technical details of the issue as well as the severity. The initial $10k payout was done on 2022-06-07, a month later.

One would imagine that this would have been escalated to some pretty senior security folks at Google before the payout was decided. That would mean that there would be some amount of discretion on Google's end as to the payout, since there would (presumably) be someone senior enough to look at this closely and authorize a higher amount even if there was some rubric that might seem to award a lower amount. Obviously this is ultimately what happened, as they eventually did increase the payout. It's a little strange to me though that this wasn't done sooner.

> One would imagine that this would have been escalated to some pretty senior security folks at Google before the payout was decided.

Bug bounties are routine. "How much do you want to pay out" is way down the list of things that leadership is focused on for these things. "How do we mitigate this" and "how does the researcher get paid" are often questions owned by different people and teams. Directors aren't swooping in to make payout decisions.

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