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Submission + - SPAM: The Voicemail Scam Spam Campaign Never Got Past OpenBSD Greylisting

badger.foo writes: "We usually don't see much of the scammy spam and malware", writes Peter Hansteen, "But that one time we went looking for them, we found a campaign where our OpenBSD greylisting setup was 100% effective in stopping the miscreants' messages." The article The Voicemail Scammers Never Got Past Our OpenBSD Greylisting shows how that scammy spam campaign looked like from behind a simple greylisting setup, with links to relevant data and articles.
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Comment Re:Is he going for irony, here? (Score 3, Informative) 190

In terms of Linux, it's not classical security through obscurity, it's security through diversity. One of the reasons Slammer was so painful a decade ago was that most institutions had a Windows monoculture. The time between one machine being infected on your network and every machine on your network being infected was about 10 minutes (a fresh Windows install on the network was compromised before it finished running Windows Update for the first time). If you'd had a network that was 50% Windows and 50% something else, then it would only have infected half of your infrastructure and you'd have been able to pull the plug on the Windows machines and start recovery. It's possible to write cross-platform malware, but it's a lot harder (though there's some fun stuff out of one of the recent DARPA programs writing exploit code that is valid x86 and ARM code, relying on encodings that are nops in one and valid in the other, interspersed with the converse). Writing malware that can attack half a dozen combinations of OS and application software is difficult.

This is why Verisign's root DNS runs 50% Linux, 50% FreeBSD and of those they run two or three userland DNS servers, so an attack on a particular OS or particular DNS server will only take out (at most) half of the machines. Even an attack on an OS combined with an independent attack on the DNS server will still leave them with about a quarter functional, which will result in a bit more latency for Internet users, but leave them functioning.

Comment Re:AV only helps if you are bad (Score 4, Interesting) 190

You got lucky. There are two problems with most Antivirus software:

Most of them still use system call interposition. They're vulnerable to a whole raft of time-of-check to time-of-use errors, so the only part that actually catches things is the binary signature checking, and that requires you to install updates more frequently than malware authors release new versions - it's a losing battle.

They run some quite buggy code in high privilege. In the last year, all of the major AV vendors have had security vulnerabilities. My favourite one was Norton, which had a buffer overflow in their kernel-mode scanner. Providing crafted data to it allowed an attacker to get kernel privilege (higher than administrator privilege on Windows). You could send someone an email containing an image attachment and compromise their system as long as their mail client downloaded the image, even if they didn't open it. It's hard to argue that software that allows that makes your computer more secure.

Comment Re: Why do we even have congress? (Score 1) 129

I always laugh at ppl like you. You will claim that far right fascists are actually liberal. For example, YOU have called W liberal. Yet, since the great depression, he is considered the most conservative president by historical ranking. Much more so than even reagan. Basically, you have to go back to Harding and Coolidge to get presidents that conservative. And now, you claim that another far right fascists like trump is a liberal even though his policies are further right than Coolidge and harding. Amazing

Comment Re: Why do we even have congress? (Score 1) 129

I agree that having THIS CONgress is worthless. Few of them , esp in the GOP have done a fucking thing. Hopefully most other ppl are more intelligent than you and know that these last 2 CONgress are in official history as America's worst congresses. Yes, historian rank them as having accomplished the least even when we need them so badly. They have submitted the fewest number of bills. Hopefully, the GOP loss BOTH houses of CONgress and the GOP then breaks up.

Comment Re:Laissez Faire Capitalist Here... (Score 1) 204

Direct government control isn't required. The good capitalist solution is not that different to the socialist solution: make homeowners own the last mile (fibre from your house to the cabinet is yours, though you may jointly own some shared trunking with your neighbours). The connections from the cabinets should be owned by public interest companies, with the shares owned by the homeowners. Providing Internet connectivity to the network would be something that you'd open to tender by any companies (for-profit or non-profit) that wanted to provide it.

The situation in most of the USA is that it's been done using the worst possible mixture of laissez-fair capitalism and central planning. Vast amounts of taxpayer money have been poured into the infrastructure, yet that infrastructure is owned by a few companies and they have geographical monopolies and are now owned by their customers, so have no incentive to improve it. Oh, and regulator capture means that it's actually illegal to fix the problem in a lot of places. You can provide an incentive in several ways:

  • Tax penalties or fines for companies that don't improve their infrastructure. Big government hammer, and very difficult to enforce usefully.
  • Try to align the ownership of the companies with their customers. Companies have to do what their shareholders want and if their shareholders want them to upgrade the network because they're getting crap service then they will.
  • Ensure that there's real competition. This is difficult because it's hard to provide any useful differentiation between providers of a big dumb pipe and the cost for new entrants into the market is very high.

Comment Re:BS (Score 1) 174

Android and iOS have very different philosophies. Android devices aim to be general-purpose computer, iOS devices aim to be extensions to a general-purpose computer. I have an Android tablet and an iPad, and I find I get a lot more use from the iPad because it doesn't try to replace my computer. There's a bunch of stuff that I can do on the Android tablet that I can't do on the iPad, but all of it is stuff that I'd be better off doing on my laptop anyway (with the one exception of an IRC client that doesn't disconnect when I switch to a different window). I still use Android for my phone, because OSMAnd~ (offline maps, offline routing, open source, and good map data) is the killer app for a smartphone for me and the iOS port is far less good.

Comment Re: The anti-science sure is odd. (Score 1) 688

Alas, it's a shame that it doesn't mean anything. The point here is that the Earth has undergone many shifts in its climate, sometimes in a startlingly short period of time

Except that the difference in temperature between the peak of the Medieval Warm Period and the bottom of the Little Ice Age were significantly smaller than the difference between the current temperature and the bottom of the Little Ice Age. The last time we saw an increase in temperature equivalent to the last 200 years it was over a period of tens of thousands of years.

Go and read a news story about an area of science that you know about and compare it to what the original research actually claimed. Now realise that press reports about climate change are no more accurate than that and go and read some of the papers. The models have been consistently refined for the last century, but the predictions are refinements (typically about specific local conditions and timescales), not complete reversals. Each year, there are more measurements that provide more evidence to support the core parts of the models.

Oh, and I don't think the words objectivist or dualistic mean what you think they mean. You can't discard evidence simply by throwing random words into a discussion.

Comment Re:Standard protocol (Score 2) 102

Considering that the entire selling point behind Signal is that it's supposed to be resistant to "an adversary like the NSA," I would think their ability to trivially associate a key with a real person would kind of turn that on its head.

Any global passive adversary can do traffic analysis on any communication network. Signal's message encryption should stand up against the NSA unless there are any vulnerabilities in the implementation that the NSA has found and not told anyone about or unless they have some magical decryption power that we don't know about (unlikely). Protection of metadata is much harder. If you connect to the Signal server and they can watch your network traffic and that of other Signal users, then they can infer who you are talking to. If they can send men with lawyers, guns, or money around to OWS then they can coerce them into recording when your client connects and from what IP, even without this.

In contrast, Tox uses a DHT, which makes some kinds of interception easier and others harder. There's no central repository mapping between Tox IDs and other identifiable information, but when you push anything to the DHT that's signed with your public key then it identifies your endpoint so a global passive adversary can use this to track you (Tox over Tor, in theory, protects you against this, but in practice there are so few people doing this that it's probably trivial to track).

No system is completely secure, but my personal thread model doesn't include the NSA taking an active interest in me - if they did that then there are probably a few hundred bugs in the operating systems and other programs that I use that they could exploit to compromise the endpoint, without bothering to attack the protocol. I'd like to be relatively secure against bulk data collection though - I don't want any intelligence or law enforcement agency to be able intercept communications unless at least one participant is actively under suspicion, because if you allow that you end up with something like Hoover's FBI or the Stazi..

Comment Re:Luddites, beware! (Score 2) 60

Currently, lorry drivers have to take statutory breaks. In the EU, they can only drive for 4.5 hours before having to take a 45-minute break. They can also only drive 9 hours per day. If you have a self-driving lorry that's only good enough for motorways (predictable traffic, well-marked lanes) and the driver can be out of the driving seat resting (even sleeping) then the vehicle can drive itself for 20 hours a day and the driver can be a passenger except when it approaches built-up areas. That would dramatically reduce the number of drivers that you'd need for a haulage fleet.

Comment Re:Standard protocol (Score 2) 102

Signal is probably secure, but all communication goes via OpenWhisperSystems' servers, as does registration (which ties your identity to your account). They can't be forced to MITM your connections (probably - unless someone finds a vulnerability in the protocol), but they can unilaterally delete your account and they can be coerced into doing so. In contrast, Tox is completely decentralised (no central servers, it's a pure peer-to-peer network). Your identity is just a public key, so the only people who can identify you on the network are people that you have told your public key to through some out-of-band mechanism (or people who can view enough of the network that they can associate a public key with something else - i.e. an adversary like the NSA).

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