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Why your Mac’s calendar app says it’s JUL 17. One patch, one line, one file. Careful with that {axe,file}, Eugene. Storm season for Microsoft. When typos make you sing for pleasure.
DOUG. Patching by hand, two kinda/sorta Microsoft zero-days, and “Careful with that file, Eugene.”
All that, and extra, on the Naked Security podcast.
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Welcome to the podcast, all people.
I’m Doug Aamoth; he’s Paul Ducklin.
Paul, how do you do at present?
DUCK. Were you making an allusion to The Pink Floyd?
DOUG. *THE* Pink Floyd, sure!
DUCK. That’s the identify by which they have been initially recognized, I consider.
DOUG. Oh, actually?
DUCK. They dropped the “The” as a result of I feel it received in the way in which.
The Pink Floyd.
DOUG. That’s a enjoyable truth!
And as luck would have it, I’ve extra Fun Facts for you…
You know we begin the present with This Week in Tech History, and we’ve received a two-fer at present.
This week, on 17 July 2002, Apple rolled out “iCal”: calendar software program that featured internet-based calendar sharing and the power to handle a number of calendars.
“JUL 17” was prominently featured on the app’s icon, which even led July 17 to develop into World Emoji Day, established in 2014.
It’s fairly a cascading impact, Paul!
DUCK. Although. in your iPhone,, you’ll discover that the icon modifications to at present’s date, as a result of that’s very helpful.
And you’ll discover that different service suppliers could or could not have chosen totally different dates, as a result of “why copy your competition”, certainly.
DOUG. Alright, let’s get into it.
We’ll discuss our first story.
This is about Zimbra and adventures in cross-site scripting.
Good previous XSS, Paul:
Zimbra Collaboration Suite warning: Patch this 0-day proper now (by hand)!
DUCK. Yes.
That’s the place you might be primarily capable of hack a web site to incorporate rogue JavaScript with out breaking into the server itself.
You carry out some motion, or create some hyperlink to that web site, that tips the location into together with content material in its reply that doesn’t simply point out, for instance, the search time period you typed in, like My Search Term, however contains further textual content that shouldn’t be there, like My search <script> rogue JavaScript </script>.
In different phrases, you trick a web site into displaying content material, with its personal URL within the tackle bar, that incorporates untrusted JavaScript in it.
And that signifies that the JavaScript you may have sneakily injected truly has entry to all of the cookies set by that web site.
So it will probably steal them; it will probably steal private knowledge; and, much more importantly, it will probably in all probability steal authentication tokens and stuff like that to let the crooks get again in subsequent time.
DOUG. OK, so what did Zimbra do on this case?
DUCK. Well, the excellent news is that they reacted shortly as a result of, in fact, it was a zero-day.
Crooks have been already utilizing it.
So they really took the marginally uncommon method of claiming, “We’ve got the patch coming. You will get it fairly soon.”
But they mentioned, fairly thoughtfully, “We understand that you may want to take action sooner rather than later.”
Now, sadly, that does imply writing a script of your individual to go and patch one line of code in a single file within the product distribution on all of your mailbox nodes.
But it’s a really small and easy repair.
And, in fact, as a result of it’s one line, you possibly can simply change the file again to what it was if it ought to trigger issues.
If you have been lifeless eager to get forward of the crooks, you possibly can do this with out ready for the complete launch to drop…
DOUG. And what a way of accomplishment, too!
It’s been some time since we’ve been capable of roll up our sleeves and simply hand-patch one thing like this.
It’s like fixing the sink on a Saturday morning… you simply really feel good afterwards.
So if I used to be a Zimbra consumer, I’d be leaping throughout this simply because I wish to get my palms on… [LAUGHTER]
DUCK. And, not like patching the sink, there was no crawling round in tight cabinets, and there was no threat of flooding your whole property.
The repair was clear and well-defined.
One line of code modified in a single file.
DOUG. Alright, so if I’m a programmer, what are some steps I can take to keep away from cross-site scripting corresponding to this?
DUCK. Well, the great factor about this bug, Doug, is it nearly acts as documentation for the type of issues it’s worthwhile to look out for in cross-site scripting.
The patch reveals that there’s a server facet element which was merely taking a string and utilizing that string inside an online type that would seem on the different finish, within the consumer’s browser.
And you possibly can see that what this system *now* does (this explicit software program is written in Java)… it calls a operate escapeXML(), which is, in the event you like, the One True Way of taking a textual content string that you just wish to show and ensuring that there are not any magic XML or HTML characters in there that might trick the browser.
In explicit: lower than (<); better than (>); ampersand (&); double quote ("); or single quote, also called apostrophe (').
Those get transformed into their long-form, secure HTML codes.
If I’ll use our normal Naked Security cliche, Doug: Sanitise thine inputs is the underside line right here.
DOUG. Oooh, I like that one!
Great. let’s transfer on to Pink Floyd, clearly… we’ve been ready for this all present.
If Pink Floyd have been cybersecurity researchers, it’s enjoyable to think about that they might have written a success tune referred to as “Careful with that file, Eugene” as an alternative, Paul. [Pink Floyd famously produced a song called Careful with that axe, Eugene.]
Google Virus Total leaks record of spooky electronic mail addresses
DUCK. Indeed.
“Careful with that file” is a reminder that generally, whenever you add a file to a web based service, in the event you decide the improper one, you may find yourself redistributing the file slightly than, for instance, importing it for safe storage.
Fortunately, not an excessive amount of hurt was achieved on this case, however this was one thing that occurred at Google’s Virus Total service.
Listeners will in all probability know that Virus Total is a very fashionable service the place, in the event you’ve received a file that both you realize it’s malware and also you wish to know what numerous totally different merchandise name it (so you realize what to go looking for in your menace logs), or in the event you assume, “Maybe I want to get the sample securely to as many vendors as possible, as quickly as possible”…
…then you definitely add to Virus Total.
The file is supposed to be made out there to dozens of cybersecurity corporations nearly instantly.
That’s not fairly the identical as broadcasting it to the world, or importing it to a leaky on-line cloud storage bucket, however the service *is* meant to share that file with different individuals.
And sadly, it appears that evidently an worker inside Virus Total by accident uploaded an inner file that was an inventory of buyer electronic mail addresses to the Virus Total portal, and to not no matter portal they have been supposed to make use of.
Now, the actual motive for scripting this story up, Doug, is that this.
Before you giggle; earlier than you level fingers; earlier than you say, “What were they thinking?”…
..cease and ask your self this one query.
“Have I ever sent an email to the wrong person by mistake?” [LAUGHTER]
That’s a rhetorical query. [MORE LAUGHTER]
We’ve all achieved it…
DOUG. It is rhetorical!
DUCK. …a few of us greater than as soon as. [LAUGHTER]
And when you’ve got ever achieved that, then what’s it that ensures you received’t add a file to the improper *server* by mistake, making an analogous type of error?
It is a reminder that there’s many a slip, Douglas, between the cup and the lip.
DOUG. Alright, we do have some ideas for the nice individuals right here, beginning with, I’d say, arguably one among our most unpopular items of recommendation: Log out from on-line accounts everytime you aren’t truly utilizing them.
DUCK. Yes.
Now, mockingly, that may not have helped on this case as a result of, as you possibly can think about, Virus Total is particularly engineered in order that anyone can *add* recordsdata (as a result of they’re meant to be shared for the better good of all, shortly, to individuals who must see them), however solely trusted clients can *obtain* stuff (as a result of the idea is that the uploads usually do include malware, so that they’re not meant to be out there to simply anyone).
But when you consider the variety of websites that you just in all probability stay logged into on a regular basis, that simply makes it extra probably that you’ll take the correct file and add it to the improper place.
If you’re not logged right into a web site and also you do attempt to add a file there by mistake, then you’ll get a login immediate…
…and you’ll defend you from your self!
It’s a fantastically easy resolution, however as you say, it’s additionally outrageously unpopular as a result of it’s modestly inconvenient. [LAUGHTER]
DOUG. Yes!
DUCK. Sometimes, nonetheless, you’ve received to take one for the staff.
DOUG. Not to shift all of the onus to the top customers: If you’re within the IT staff, think about placing controls on which customers can ship what types of recordsdata to whom.
DUCK. Unfortunately, this type of blocking is unpopular, in the event you like for the other-side-of-the-coin motive to why individuals don’t like logging out of accounts once they’re not utilizing them.
When IT comes alongside and says, “You know what, we’re going to turn on the Data Loss Prevention [DLP] parts of our cybersecurity endpoint product”…
…individuals go, “Well, that’s inconvenient. What if it gets in the way? What if it interferes with my workflow? What if it causes a hassle for me? I don’t like it!”
So, loads of II
T departments could find yourself staying slightly bit shy of doubtless interfering with workflow like that.
But, Doug, as I mentioned within the article, you’ll at all times get a second likelihood to ship a file that wouldn’t exit the primary time, by negotiating with IT, however you by no means get the prospect to unsend a file that was not imagined to exit in any respect.
DOUG. [LAUGHS] Exactly!
Alright, good ideas there.
Our final story, however actually not least.
Paul, I don’t must remind you, however we must always remind others…
…utilized cryptography is tough, safety segmentation is tough, and menace searching is tough.
So what does that each one must do with Microsoft?
Microsoft hit by Storm season – a story of two semi-zero days
DUCK. Well, there’s been loads of information within the media not too long ago about Microsoft and its clients getting turned over, hit up, probed and hacked by a cybercrime group generally known as Storm.
And one a part of this story goes round 25 organisations that had these rogues inside their Exchange enterprise.
They’re sort-of zero-days.
Now, Microsoft revealed a reasonably full and pretty frank report about what occurred, as a result of clearly there have been at the very least two blunders by Microsoft.
The means they inform the story can educate you an terrible lot about menace searching, and about menace response when issues go improper.
DOUG. OK, so it seems to be like Storm received in by way of Outlook Web Access [OWA] utilizing a bunch of usurped authentication tokens, which is mainly like a brief cookie that you just current that claims, “This person’s already logged in, they’re legit, let them in.”
Right?
DUCK. Exactly, Doug.
When that type of factor occurs, which clearly is worrying as a result of it permits the crooks to bypass the robust authentication part (the bit the place it’s important to kind in your username, kind in your password, then do a 2FA code; or the place it’s important to current your Yubikey; or it’s important to swipe your sensible card)…
…the plain assumption, when one thing like that occurs, is that the particular person on the different finish has malware on a number of of their customers’ computer systems.
Malware does get an opportunity to take a peek at issues like browser content material earlier than it will get encrypted, which signifies that it will probably leech out authentication tokens and ship them off to the crooks the place they are often abused later.
Microsoft admit of their report that that this was their first assumption.
And if it’s true, it’s problematic as a result of it signifies that Microsoft and people 25 individuals must go working round making an attempt to do the menace searching.
But if that *isn’t* the reason, then it’s necessary to determine that out early on, so that you don’t waste your individual and everybody else’s time.
Then Microsoft realised, “Actually it looks as though the crooks are basically minting their own authentication tokens, which suggests that they must have stolen one of our supposedly secure Azure Active Directory token-signing keys.”
Well, that’s worrying!
*Then* Microsoft realised, “These tokens are actually apparently digitally signed by a signing key that’s only really supposed to be used for consumer accounts, what are called MSAs, or Microsoft accounts.”
In different phrases, the type of signing key that might be used to create an authentication token, say in the event you or I have been logging into our private Outlook.com service.
Oh, no!
There’s one other bug that signifies that it’s attainable to take a signed authentication token that’s not imagined to work for the assault they take note of, after which go in and fiddle with individuals’s company electronic mail.
So, that each one sounds very dangerous, which in fact it’s.
But there’s an upside…
…and that’s the irony that as a result of this wasn’t imagined to work, as a result of MSA tokens aren’t imagined to work on the company Azure Active Directory facet of the home, and vice versa, nobody at Microsoft had ever bothered writing code to make use of one token on the opposite taking part in area.
Which meant that each one of those rogue tokens stood out.
So there was at the very least an enormous, seen crimson flag for Microsoft’s menace searching.
Fixing the issue, luckily, as a result of it’s a cloud facet drawback, signifies that you and I don’t must rush out and patch our methods.
Basically, the answer is: disown the signing key that’s been compromised, so it doesn’t work anymore, and whereas we’re about it, let’s repair that bug that enables a shopper signing key to be legitimate on the company facet of the Exchange world.
It sort-of is a little bit of an “All’s well that ends well.”
But as I mentioned, it’s a giant reminder that menace searching usually includes much more work than you may at first assume.
And in the event you learn by means of Microsoft’s report, you possibly can think about simply how a lot work went into this.
DOUG. Well, within the spirit of catching every thing, let’s hear from one among our readers within the Comment of the Week.
I can let you know first-hand after doing this for the higher a part of ten years, and I’m positive Paul can let you know first-hand after doing this in hundreds and hundreds of articles…
…typos are a lifestyle for a tech blogger, and in the event you’re fortunate, generally you find yourself with a typo so good that you just’re loath to repair it.
Such is the case with this Microsoft article.
Reader Dave quotes Paul as writing “which seemed to suggest that someone had indeed pinched a company singing [sic] key.”
Dave then follows up the quote by saying, “Singing keys rock.”
Exactly! [LAUGHTER]
DUCK. Yes, it took me some time to understand that’s a pun… however sure, “singing key.” [LAUGHS]
What do you get in the event you drop a crate of saxophones into a military camp?
DOUG. [LAUGHS]
DUCK. [AS DRY AS POSSIBLE] A-flat main.
DOUG. [COMBINED LAUGH-AND-GROAN] Alright, superb.
Dave, thanks for pointing that out.
And we do agree that singing keys rock; signing keys much less so.
If you may have an attention-grabbing story, remark or query you’d wish to submit, we’d like to learn it on the podcast.
You can electronic mail ideas@sophos.com, you possibly can touch upon any one among our articles, or you possibly can hit us up on social: @nakedsecurity.
That’s our present for at present; thanks very a lot for listening.
For Paul Ducklin, I’m Doug Aamoth, reminding you, till subsequent time, to…
BOTH. Stay safe!
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