> So, to summarize: the LightSpeed bug was fixed in iOS 12 with a patch that didn't address the root cause and instead just turned the race condition double-free into a memory leak. Then, in iOS 13, this memory leak was identified as a bug and "fixed" by reintroducing the original bug, again without addressing the root cause of the issue. And this security regression could have been found trivially by running the ori…
How to unc0ver a 0-day in 4 hours or less
51–60 of 120 posts
Re: How to unc0ver a 0-day in 4 hours or less
#52Since this always comes up, here's an overview I made several weeks ago about where Project Zero focuses their efforts: All counts are rough numbers. Project zero posts: Google: 24 Apple: 28 Microsoft: 36 I was curious, so I poked around the project zero bug tracker to try to find ground truth about their bug reporting: https://bugs.chromium.org/p/project-zero/issues/list For all issues, including closed: product=And…
Most experts have expertise on only one or two different OS's or bits of software. The found issues will strongly depend who happens to be on the Google Project Zero team at the moment.
My post was to counter folks thinking P0 is a Google hit job, which seems to come up frequently on HN.
Re: How to unc0ver a 0-day in 4 hours or less
#53> So, to summarize: the LightSpeed bug was fixed in iOS 12 with a patch that didn't address the root cause and instead just turned the race condition double-free into a memory leak. Then, in iOS 13, this memory leak was identified as a bug and "fixed" by reintroducing the original bug, again without addressing the root cause of the issue. And this security regression could have been found trivially by running the ori…
Isn't the root cause that two entities can free the given memory and have no high level coordination of it? It basically states this in the article.
Re: How to unc0ver a 0-day in 4 hours or less
#54Re: How to unc0ver a 0-day in 4 hours or less
#55Why is he doing that work? Does Apple not fix every jailbreak exploits by themselves?
In this case, it looks like there is a point to it: > My goal in trying to identify the bug used by unc0ver was to demonstrate that obfuscation does not block attackers from quickly weaponizing the exploited vulnerability.
And in fact, I will argue that this looks like it worked great: yes, someone--and of course, likely many people working in shadowy areas of organized crime, arms dealers, and government contractors--figured it out in hours, and they could have been malicious and used it to attack others. But the real question is then how many such attackers you enable and what their goals are. If you publish an exploit as open source code along with the tool (which some people have done in the past :/), you allow almost any idiot "end" developer to become an attacker: millions of people at low effort instead of thousands or hopefully even only hundreds (when combined with incentives, not just ability).
If you publish a closed source binary with obfuscation--one which is restricted to a limited usage profile (like if nothing else it isn't in the right UI form to "trick" someone into triggering it, or where what it ostensibly "does" is too blatantly noticeable) you limit the number of people who both have the time and incentives to work out the vulnerability and then rebuild a stable exploit for it (which is hard) down to a small number of people, almost none of whom (including the attackers) who are then incentivized to publish a blog post (or certainly code) until at least months after it gets fixed (as was the case here).
And so, as someone who had been sitting in the core of this community--where everyone is wearing a grey hat, the vendors are the "bad guys", and "responsible disclosure" is being complicit in a dystopia--and dealing with these ethical challenges for a decade, my personal opinion is "please never ever drop a zero day on the world without it being a closed source obfuscated binary" unless you want to drop the barrier to entry so low that you have creepy software engineers quickly using the exploit against their ex-spouse as opposed to "merely" advanced attackers using the vulnerability for corporate or government espionage.
Re: How to unc0ver a 0-day in 4 hours or less
#56Checkra1n, another iOS exploit (although it's more impressively a bootrom exploit), is mentioned. You can see slides on it from 2019 here: https://iokit.racing/oneweirdtrick.pdf (The One Weird Trick SecureROM Hates)
Re: How to unc0ver a 0-day in 4 hours or less
#57> By 1 AM, I had sent Apple a POC and my analysis. > Still, I'm very happy that Apple patched this issue in a timely manner once the exploit became public. Sh- should we be happy Apple fixed this so quickly? unc0ver allows consumers to get more out of their Apple devices, and Apple's fix isn't really optional (unless you disable auto-updates and tap "Later" on every update notification). Is this exploit even an issue…
The second paragraph of the article covers this: > I wanted to find the vulnerability used in unc0ver and report it to Apple quickly in order to demonstrate that obfuscating an exploit does little to prevent the bug from winding up in the hands of bad actors.
Of course if he was this talented, surely he would routinely diff new kernel versions and realize the old bug had been reintroduced before having to rediscover it in a jailbreak?
Re: How to unc0ver a 0-day in 4 hours or less
#58Earlier quoted context omitted.
In this case, it looks like there is a point to it: > My goal in trying to identify the bug used by unc0ver was to demonstrate that obfuscation does not block attackers from quickly weaponizing the exploited vulnerability.
We all know obfuscation isn't some magic "no one knows how this works now" trick: the goal is to buy time while people are forced to work though your defense and to slow down the proliferation. Now, the "problem" with this is that some people are just really good at pulling things apart, and so one person can spend four hours attacking it and then tell the world how it worked. But then it is more a matter of incentiv…
Obviously you have a better understanding of the iOS jailbreak scene than I ever will, but I still have to say I disagree with this ethical viewpoint. Personally, I'd rather run an open source exploit chain than obfuscated binaries from parties I do not know that are difficult to be sure are safe. Thankfully in the case of unc0ver that is not an issue anymore, but in the past it has been an issue for longer time periods. OTOH, if there is really a moral dilemma in releasing 0days as open source specifically because of the small time abusers and not nation state adversaries, I don't understand how this moral quandary doesn't mean you can never ethically release an iBoot/more generally any bootrom exploit, for example.
I'm genuinely curious how many abusive people are motivated enough to come up with a creepy use for a tethered jailbreak. I know it's possible, but short of rolling your own stalkerware, it really doesn't seem too straightforward?
Re: How to unc0ver a 0-day in 4 hours or less
#59> By 1 AM, I had sent Apple a POC and my analysis. > Still, I'm very happy that Apple patched this issue in a timely manner once the exploit became public. Sh- should we be happy Apple fixed this so quickly? unc0ver allows consumers to get more out of their Apple devices, and Apple's fix isn't really optional (unless you disable auto-updates and tap "Later" on every update notification). Is this exploit even an issue…
It’s always a snake eating it’s tail scenario with jailbreaking. Apple takes popular tweaks and integrates them with the next IOS. Side-loading isn’t that bad but the method keeps changing...Usually for the better. Jail breaking cuts into their profit a small amount because the community is small. https://www.reddit.com/r/jailbreak The benefits are very much worth it though. Most have had iOS 13 features since iOS 11…
Not even to fan boy, but half of those are things that android did from the go and the rest have been added or are generally easy to do.
Re: How to unc0ver a 0-day in 4 hours or less
#60> By 1 AM, I had sent Apple a POC and my analysis. > Still, I'm very happy that Apple patched this issue in a timely manner once the exploit became public. Sh- should we be happy Apple fixed this so quickly? unc0ver allows consumers to get more out of their Apple devices, and Apple's fix isn't really optional (unless you disable auto-updates and tap "Later" on every update notification). Is this exploit even an issue…
It’s always a snake eating it’s tail scenario with jailbreaking. Apple takes popular tweaks and integrates them with the next IOS. Side-loading isn’t that bad but the method keeps changing...Usually for the better. Jail breaking cuts into their profit a small amount because the community is small. https://www.reddit.com/r/jailbreak The benefits are very much worth it though. Most have had iOS 13 features since iOS 11…