Author: Jonathan Bennett

526 Articles

This Week In Security: Zimbra, Lockbit 2, And Hacking NK

February 11, 2022 by 9 Comments

Unknown attackers have been exploiting a 0-day attack against the Zimbra e-mail suite. Researchers at Volexity first discovered the attack back in December of last year, detected by their monitoring infrastructure. It’s a cross-site scripting (XSS) exploit, such that when opening a malicious link, the JavaScript running on the malicious page can access a logged-in Zimbra instance. The attack campaign uses this exploit to grab emails and attachments and upload them to the attackers. Researchers haven’t been able to positively identify what group is behind the attacks, but a bit of circumstantial evidence points to a Chinese group. That evidence? Time zones. The attacker requests all use the Asia/Hong_Kong time zone, and the timing of all the phishing emails sent lines up nicely with a work-day in that time zone.

Zimbra has responded, confirming the vulnerability and publishing a hotfix for it. The campaign seems to have been targeted specifically against European governments, and various media outlets. If you’re running a Zimbra instance, make sure you’re running at least 8.8.15.1643980846.p30-1.

LockBit 2.0

Because security professionals needed something else to keep us occupied, the LockBit ransomware campaign is back for a round two. This is another ransomware campaign run in the as-a-Service pattern — RAAS. LockBit 2 has caught enough attention, that the FBI has published a FLASH message (PDF) about it. That’s the FBI Liaison Alert System, in the running for the worst acronym. (Help them figure out what the “H” stands for in the comments below!)

Like many other ransomware campaigns, LockBit has a list of language codes that trigger a bail on execution — the Eastern European languages you would expect. Ransomware operators have long tried not to poison their own wells by hitting targets in their own back yards. This one is being reported as also having a Linux module, but it appears that is limited to VMWare ESXi virtual machines. A series of IoCs have been published, and the FBI are requesting any logs, ransom notes, or other evidence possibly related to this campaign to be sent to them if possible. Continue reading “This Week In Security: Zimbra, Lockbit 2, And Hacking NK” →

This Week In Security: Samba, Wormhole Crypto Heist, And A Bogus CVE

February 4, 2022 by 6 Comments

Samba has a very serious vulnerability, CVE-2021-44142, that was just patched in new releases 4.13.17, 4.14.12, and 4.15.5. Discovered by researchers at TrendMicro, this unauthenticated RCE bug weighs in at a CVSS 9.9. The saving grace is that it requires the fruit VFS module to be enabled, which is used to support MacOS client and server interop. If enabled, the default settings are vulnerable. Attacks haven’t been seen in the wild yet, but go ahead and get updated, as PoC code will likely drop soon.

Crypto Down the Wormhole

One notable selling point to cryptocurrencies and Web3 are smart contracts, little computer programs running directly on the blockchain that can move funds around very quickly, without intervention. It’s quickly becoming apparent that the glaring disadvantage is these are computer programs that can move money around very quickly, without intervention. This week there was another example of smart contracts at work, when an attacker stole $326 million worth of Ethereum via the Wormhole bridge. A cryptocurrency bridge is a service that exists as linked smart contracts on two different blockchains. These contracts let you put a currency in on one side, and take it out on the other, effectively transferring currency to a different blockchain. Helping us make sense of what went wrong is [Kelvin Fichter], also known appropriately as [smartcontracts].

When the bridge makes a transfer, tokens are deposited in the smart contract on one blockchain, and a transfer message is produced. This message is like a digital checking account check, which you take to the other side of the bridge to cash. The other end of the bridge verifies the signature on the “check”, and if everything matches, your funds show up. The problem is that one one side of the bridge, the verification routine could be replaced by a dummy routine, by the end user, and the code didn’t catch it.

It’s a hot check scam. The attacker created a spoofed transfer message, provided a bogus verification routine, and the bridge accepted it as genuine. The majority of the money was transferred back across the bridge, where other user’s valid tokens were being held, and the attacker walked away with 90,000 of those ETH tokens. Continue reading “This Week In Security: Samba, Wormhole Crypto Heist, And A Bogus CVE” →

This Week In Security: Geopolitical Hacktivism, Antivirus Mining, And Linux Malware

January 28, 2022 by 15 Comments

The CIA Hacktivists have launched a sort of ransomware campaign against the Belarusian rail system, but instead of cryptocurrency, they want the release of political prisoners and removal of Russian soldiers. This could be called an example of cyber-terrorism, though there is a reasonable theory that this is a state-sponsored hack, masquerading as hacktivism. What does seem certain is that something has interrupted rail transit, and a group on Twitter has produced convincing proof of a breach.

Your Antivirus Now Includes a CryptoMiner

Don’t look now, but your latest update of Norton 360 or Avira may have installed a cryptocurrency mining module. The silver lining is that some sanity has been retained, and you have to opt-in to the crypto scheme before your machine starts spending its spare cycles on mining. For users who do, they’re put into a mining pool, making for small payouts for most hardware. Norton, naturally, takes a 15% fee off the top for their trouble.

The State of Linux Malware

There used to be an adage that Linux machines don’t get malware. That’s never really been quite true, but the continued conquest of the server landscape has had the side effect of making Linux malware an even greater danger. Crowdstrike has seen a 35% increase in Linux malware in 2021, with three distinct categories leading the charge: XorDDoS, Mozi, and Mirai. Continue reading “This Week In Security: Geopolitical Hacktivism, Antivirus Mining, And Linux Malware” →

This Week In Security: NetUSB, HTTP.sys, And 2013’s CVE Is Back

January 21, 2022 by 2 Comments

Let’s imagine a worst case situation for home routers. It would have to start with a port unintentionally opened to the internet, ideally in a popular brand, like Netgear. For fun, let’s say it’s actually a third-party kernel module, that is in multiple router brands. This module would then need a trivial vulnerability, say an integer overflow on the buffer size for incoming packets. This flaw would mean that the incoming data would write past the end of the buffer, overwriting whatever kernel data is there. So far, this exactly describes the NetUSB flaw, CVE-2021-45608.

Because red teams don’t get their every wish, there is a catch. While the overflow is exceptionally easy to pull off, there isn’t much wiggle room on where the data gets written. There’s no remote code execution Proof of Concept (PoC) yet, and [Max Van Amerongen], who discovered the flaw, says it would be difficult but probably not impossible to pull off. All of this said, it’s a good idea to check your router for open ports, particularly non-standard port numbers. If you have a USB port on your router, check for updates.

Windows HTTP.sys Problem

A serious problem has been announced in Windows Server 2019 and Windows 10, with some versions vulnerable in their default configurations. The problem is in how Windows handles HTTP Trailer packets, which contain extra information at the end of normal HTTP transfers. There is a PoC available that demonstrates a crash. It appears that an additional information leak vulnerability would have to be combined with this one to produce a true exploit. This seems to be a different take on CVE-2021-31166, essentially exploiting the same weakness, and working around the incomplete fix. This issue was fixed in the January patch set for Windows, so make sure you’re covered. Continue reading “This Week In Security: NetUSB, HTTP.sys, And 2013’s CVE Is Back” →

This Week In Security: NPM Vandalism, Simulating Reboots, And More

January 14, 2022 by 33 Comments

We’ve covered quite a few stories about malware sneaking into NPM and other JavaScript repositories. This is a bit different. This time, a JS programmer vandalized his own packages. It’s not even malware, perhaps we should call it protestware? The two packages, colors and faker are both popular, with a combined weekly download of nearly 23 million. Their author, [Marak] added a breaking update to each of them. These libraries now print a header of LIBERTY LIBERTY LIBERTY, and then either random characters, or very poor ASCII art. It’s been confirmed that this wasn’t an outside attacker, but [Marak] breaking his own projects on purpose. Why?

It seems like this story starts back in late 2020, when [Marak] lost quite a bit in a fire, and had to ask for money on Twitter. Edit: Thanks to commenter [Jack Dansen] for pointing out an important detail that was missing. Marak was charged for reckless endangerment, and was suspected for possible terrorism aspirations, as bomb-making materials were found in his burned-out apartment. Two weeks later, he tweeted that billions were being made off open source devs’ work, citing a FAANG leak. FAANG is a reference to the big five American tech companies: Facebook, Apple, Amazon, Netflix, and Google. The same day, he opened an issue on Github for faker.js, throwing down an ultimatum: “Take this as an opportunity to send me a six figure yearly contract or fork the project and have someone else work on it.”
Continue reading “This Week In Security: NPM Vandalism, Simulating Reboots, And More” →

This Week In Security: Y2K22, Accidentally Blocking 911, And Bug Alert

January 7, 2022 by 45 Comments

If you had the misfortune of running a Microsoft Exchange server this past week, then you don’t need me to tell you about the Y2K22 problem. To catch rest of us up, when Exchange tried to download the first malware definitions update of 2022, the version number of the new definitions triggered a crash in the malware detection engine. The date is represented as the string 2201010001, where the first two digits represent the year. This string gets converted to a signed long integer, which maxes out at 2,147,483,647. The integer overflows, and the result is undefined behavior, crashing the engine. The server fails safe, not processing any messages without a working malware engine, which means that no e-mail gets through. Happy new year!
Continue reading “This Week In Security: Y2K22, Accidentally Blocking 911, And Bug Alert” →

Getting Back That YouTube Dislike Button

January 2, 2022 by 40 Comments

Ah, Google. Very few companies have mastered the art of creating amazing technology and products, and then so effectively abandoning and mishandling them. Case in point, YouTube. Citing “dislike attacks”, which are coordinated down-voting of particular videos, YouTube opted to hide the dislike counter on all videos. It could be pointed out that dislikes still impact the recommendation algorithm the same way they always have, and that creators still see their dislike counts on their own dashboard.

There might be something to the idea that YouTube doesn’t like the notoriety of their Rewind videos leading the dislike count, with 2018 at nearly 20 million. There may even be validity in the theory that corporate partners don’t like visible dislike numbers on their videos. Regardless, YouTube made the change, and people hate it. Their platform, so nothing you can do about it, right?

“Life, uh, uh, finds a way,” to quote my favorite fictional mathematician. Yes, a hacker, one of us, has figured out a workaround. [Dmitrii Selivanov] has put together the “Return YouTube Dislike” browser extension, which does a couple of things. First, it is pulling archived data about videos, taking advantage of the gap in time between the official announcement, and the removal of the dislike API.

But for new videos? That’s where things are harder. If you install the extension, your video likes and dislikes are tracked, and the combined user data is used to extrapolate an estimated dislike count on any given video. [Dimitrii] is also working on a way to allow individual channels to share their stats with the project, to give more official numbers for their videos.

The extension is open source, and the Chrome web store shows over a million users. Linus Tech Tips, along with a bunch of other channels, have covered this, so check out their videos for more.

Continue reading “Getting Back That YouTube Dislike Button” →