Microsoft says email spammers are adopting ASCII smuggling | Hacker News Reader

Microsoft says email spammers are adopting ASCII smuggling

arstechnica.com

68 pointsutiiiD36 comments

Getting bombarded by "Paypal" <somethingsomething@something.onmicrosoft.com> spam for months and Microsoft (outlook) can't handle that. This is beyond their level.

For anyone still fortunately-unfamilier: Microsoft has some supposedly limited-purpose e-mail notifications and invites which are quasi-legitimate... but they failed on the UX level, allowing spammers to pack seemingly-innocent fields like Organization Name with content that becomes the (apparent) main content of the e-mail.

Yeah; imagine getting not junk...actual PayPal phishing emails, daily, multiple, from onmicrosoft.com (owned by Microsoft), in Outlook (owned by Microsoft), and report phishing does nothing.

> The root domain onmicrosoft.com is owned and managed by Microsoft Corporation, which uses it as the default domain for Microsoft 365 and Azure cloud environments

imagine that these people have most money in the world. Bill Gates (owns MS). Elon Musk (owns / owned PayPal). Now stop wondering why and start using other services.

That seems like a non-sequitur.

Parent-poster wasn't lamenting monopolies, they were just incredulous that some supposedly well-resourced and integrated company still can't get its act together to stop a well-understood problem.

As a common-name@gmail.com holder, unfiltered spam is less commonplace than a) websites adding me to distribution/mailing lists without verifying I was the person to type it in, b) people who either accidentally transform their address into mine, or forget part of their address.

These are from all parts of the globe. I have access to bank accounts in South America, Disney employee music royalty earnings tax disclosures and forms, European subscribers online platforms, AWS account recovery options, veterinarian records in Studio City, private school/PTA leadership website access in Mountain View.

I stopped trying to return unopened mail, nobody cared.

I don't do anything with any of this because I'm not a giant fool, but people, have your users verify their email addresses before you trust them.

Ha! Me too. I have first.last@gmail.com, which means firstlast@gmail.com (without the dot) also maps to my email account. (first and last are placeholders for my actual name, of course).

I get lots of stuff intended for other people (including a mildly famous person with my name whose actual email address is last.first@gmail.com).

A few years ago, someone set up a shopify account with my email address. Overnight while I slept, the shopify account was created, did some bad stuff, and got suspended for fraudulent activity. The whole story was told through the series of emails coming in over a couple of hours. Shopify did not required the fraudster to confirm the email address to activate the account.

When I asked shopify to unlink my email address from this fraudster account, they instructed me to click on the "forgot my password" link on their login page, click on the "change password" link in the resulting email, and then login and remove my email from the account. This was my only option, they claimed. Obviously, I was never going to connect my IP address with some fraudster's Shopify account, so I just left it as-is.

I guess services feel it adds too much "friction" to force a user to verify the specified email account before allowing them to use the service.

A few years ago, during a particularly spam heavy period, I got pissed at Google's ineptness at combating spam, and decided to have a think about how I could get rid of the problem for good.

What I arrived at:

- I should never hand out my actual email address. As in, should be all proxied, every contact reaching me via a different address only known to them. Ideally, these aliases would be generated using a CSPRNG, and would be of sufficient length. Allows for tracing contact provenance in "space".

- I should rotate that address periodically, if possible. Allows for tracing contact provenance in "time".

Together, this would tell me who's the source of any particular influx of strange mails, and when did they leak the contact address provided to them (willfully or otherwise). This would enable me to separate the wheat from the chaff and nuke that address for good, inform the other party, etc.

I was really taken by this idea, even wondered why this has not been baked into the underlying protocols over the years, to make it readily deployed and available for all, making it effortless.

Because boy is there an effort involved! Several years later, I now avoid spam mail by simply no longer reading my emails anymore...

Sometimes I wonder what corporate IT thinks when I pass their anti-phishing test a month after the test campaign.

I estimate that I can identify 99.5% of spam by the subject line alone. I don't know why its such a hard problem, and why renewal notices for Norton 360 Premium sent to "Customer" from a random gmail address keep passing as legitimate email.

Hell, just block all emails mentioning Norton 360. Wouldn't be any great loss to the world.

But what I don't understand is MS letting these through the spam filter but randomly, in a thread between myself and another person both using MS account emails, sending a single email in that thread to spam.

>Several years later, I now avoid spam mail by simply no longer reading my emails anymore...

I realized the other day I haven't even checked my main email in months and I missed absolutely noting important.

Except the H

One thing to be careful of is email hosts that dump your account after x months of inactivity. Logging in once in a while is good, got burned by this once.

Check out spamgourmet; they came up with roughly the same thing over 25 years ago, and implemented it, and handed it out to all for free. ;)

Why not sanitize and denormalize (or whatever it's called) the text before feeding it to the spam filter? Or the LLM prompt?

Do you have any evidence they didn't?

My suspicion is that the spam filter programmers didn't do a comprehensive evaluation of every code point on every plane of Unicode because... well that's a massive job. So your "sanitize and denormalize" tasks are actually massive mappings which were likely imperfectly created.

I'm basing my comment on the article. Since they are susceptible to ASCII smuggling, they can't have been doing unicode normalization.

The task isn't that massive. Python's unicodedata (for example) contains all the info already. Including the normalization (not denormalization as I wrote before) function.

Is there something I'm missing?

Throwing it as-is into a simple bayesian filter works great too - nobody honest writes fun&zwsp;ding.

This is what I always tell people. If something is obviously sketchy, don't bother trying to make it safe. Just discard it. No reason to play the attacker's game. (Obviously you need to know what inputs are sketchy vs just uncommon, like people with a single quote in their last name)

Currently, my experience is that spam filters often block non-spam messages and allow many spam messages through. Platform notifications are spam! Yes, even if I signed up for it, I agreed to be contacted by the company, I never agreed to be spammed by them 100 messages a day.

Platforms should aggregate all their notifications into a single daily or weekly email unless the thing is marked urgent! It's not difficult to do!

Microsoft is a spammer and spamming platform themselves so this seems like a distraction.

Whoever thought it was acceptable to have a string of text that renders something unreadable or not immediately obvious to the human eye, was a complete moron.

I realize ASCII was limited, but one thing I like about it is I can understand every single character code, and program to handle all the edge cases with certainty.

The tags were needed for language indication to control CJK glyph variants. Flag emoji were grafted onto this scheme. The key is that tag sequences have to start with a valid introductory codepoint. Simple enough to strip out anything that isn't a flag.

> Simple enough to strip out anything that isn't a flag.

But it's not simple enough for every company/app to independently research the entire Unicode code point space (which is MASSIVE) to find out what kinds of "fix ups" that app needs to do to clean the data it consumes.

It's complicated or at least has difficult tradeoffs. Maybe you invest a lot of time carefully surveying all of the Unicode planes and decide which ones you care to keep unchanged and which ones you filter/strip. For every code point you reject or change, there is going to be some user who is confused or dissatisfied with the limitations of your app.

“Everyone knew” that in-band signaling was an awful, horribly insecure idea… until we found magic math that couldn’t “think” any other way.

I don’t think it’s reasonable to blame the Unicode authors for not anticipating this turn of events.

Maybe you intended to reply to my comment's parent? I don't necessarily disagree.

But also, according to the Ars article comment describing the Unicode character range, it has been deprecated, so maybe someone involved in the Unicode standard saw problems with it.

Even classic ASCII has "unreadable" control codes, but to be fair they would not be confused with text even by an LLM. Well probably not.

Sure, but there's a big difference between a handful (or a few dozen), compared to thousands of obscure code points. One I can learn, the other I need to dedicate an unreasonably large chunk of my life to fully understand.

> I realize ASCII was limited, but one thing I like about it is I can understand every single character code

It's great for teaching and other things, but everyday life is filled with many characters, is the suggestion we'd have one ASCII per language where there is more distinct characters, or what would we do? I don't see what else we could have done, that would have worked for the world, but I'm curious to hear ideas.

A good start would be being more judicious about what sort of "characters" and functionality to include.

The top comment (the Staff Highlighted one) explains why this range of code point exists.

There was a rationale (ISO country codes to modify a flag to display that national flag).

Maybe the problem wasn't the proposal, but the lack of the ability for others to reject it for being insecure.

Why does a line of text need to include a flag in the first place?

If you want an image, embed an image.

Are you complaining about the existence of emojis? Get off my lawn, old man!

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