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Patch Tuesday, Good Riddance 2020 Edition

Microsoft today issued its final batch of security updates for Windows PCs in 2020, ending the year with a relatively light patch load. Nine of the 58 security vulnerabilities addressed this month earned Microsoft’s most-dire “critical” label, meaning they can be abused by malware or miscreants to seize remote control over PCs without any help from users.

Mercifully, it does not appear that any of the flaws fixed this month are being actively exploited, nor have any them been detailed publicly prior to today.

The critical bits reside in updates for Microsoft Exchange Server, Sharepoint Server, and Windows 10 and Server 2016 systems. Additionally, Microsoft released an advisory on how to minimize the risk from a DNS spoofing weakness in Windows Server 2008 through 2019.

Some of the sub-critical “important” flaws addressed this month also probably deserve prompt patching in enterprise environments, including a trio of updates tackling security issues with Microsoft Office.

“Given the speed with which attackers often weaponize Microsoft Office vulnerabilities, these should be prioritized in patching,” said Allan Liska, senior security architect at Recorded Future. “The vulnerabilities, if exploited, would allow an attacker to execute arbitrary code on a victim’s machine. These vulnerabilities affect Microsoft Excel 2013 through 2019, Microsoft 365 32 and 64 bit versions, Microsoft Office 2019 32 and 64 bit versions, and Microsoft Excel for Mac 2019.”

We also learned this week that Redmond quietly addressed a scary “zero-click” vulnerability in its Microsoft Teams platform that would have let anyone execute code of their choosing just by sending the target a specially-crafted chat message to a Teams users. The bug was cross-platform, meaning it could also have been used to deliver malicious code to people using Teams on non-Windows devices.

Researcher Oskars Vegeris said in a proof-of-concept post to Github that he reported the flaw to Microsoft at the end of August, but that Microsoft didn’t assign the bug a Common Vulnerabilities and Exposure (CVE) rating because it has a policy of not doing so for bugs that can be fixed from Microsoft’s end without user interaction.

According to Vegeris, Microsoft addressed the Teams flaw at the end of October. But he said the bug they fixed was the first of five zero or one-click remote code execution flaws he has found and reported in Teams. Reached via LinkedIn, Vegeris declined to say whether Microsoft has yet addressed the remaining Teams issues.

Separately, Adobe issued security updates for its Prelude, Experience Manager and Lightroom software. There were no security updates for Adobe Flash Player, which is fitting considering Adobe is sunsetting the program at the end of the year. Microsoft is taking steps to remove Flash from its Windows browsers, and Google and Firefox already block Flash by default.

It’s a good idea for Windows users to get in the habit of updating at least once a month, but for regular users (read: not enterprises) it’s usually safe to wait a few days until after the patches are released, so that Microsoft has time to iron out any chinks in the new armor.

But before you update, please make sure you have backed up your system and/or important files. It’s not uncommon for a Windows update package to hose one’s system or prevent it from booting properly, and some updates have been known to erase or corrupt files.

So do yourself a favor and backup before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

And if you wish to ensure Windows has been set to pause updating so you can back up your files and/or system before the operating system decides to reboot and install patches on its own schedule, see this guide.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.

IRS to Make ID Protection PIN Open to All

The U.S. Internal Revenue Service (IRS) said this week that beginning in 2021 it will allow all taxpayers to apply for an identity protection personal identification number (IP PIN), a single-use code designed to block identity thieves from falsely claiming a tax refund in your name. Currently, IP PINs are issued only to those who fill out an ID theft affidavit, or to taxpayers who’ve experienced tax refund fraud in previous years.

Tax refund fraud is a perennial problem involving the use of identity information and often stolen or misdirected W-2 forms to electronically file an unauthorized tax return for the purposes of claiming a refund in the name of a taxpayer.

Victims usually first learn of the crime after having their returns rejected because scammers beat them to it. Even those who are not required to file a return can be victims of refund fraud, as can those who are not actually due a refund from the IRS.  

Many of the reasons why refund fraud remains a problem have to do with timing, and some of them are described in more detail here. But the short answer is the IRS is under tremendous pressure to issue refunds quickly and to minimize “false positives” (flagging legitimate claims as fraud) — even when it may not yet have all of the information needed to accurately distinguish phony filings from legitimate ones.

One way the IRS has sought to stem the flow of bogus tax refund applications is to issue the IP PIN, which is a six-digit number assigned to eligible taxpayers to help prevent the use of their Social Security number on a fraudulent income tax return. Each PIN is good only for the tax year for which it was issued.

But up until now, the IRS has restricted who can apply for an IP PIN, although it has over the past few years issued them proactively to some taxpayers as part of a multi-state experiment to determine if doing so more widely might reduce the overall incidence of refund fraud.

The IRS says it will make its Get IP PIN tool available to all taxpayers in mid-January. Until then, if you haven’t already done so you should plant your flag at the IRS by stepping through the agency’s “secure access authentication” process.

Creating an account requires supplying a great deal of personal data; the information that will be requested is listed here.

The signup process requires one to validate ownership of a mobile phone number in one’s name, and it will reject any voice-over-IP-based numbers such as those tied to Skype or Google Voice. If the process fails at this point, the site should offer to send an activation code via postal mail to your address on file.

Patch Tuesday, November 2020 Edition

Adobe and Microsoft each issued a bevy of updates today to plug critical security holes in their software. Microsoft’s release includes fixes for 112 separate flaws, including one zero-day vulnerability that is already being exploited to attack Windows users. Microsoft also is taking flak for changing its security advisories and limiting the amount of information disclosed about each bug.

Some 17 of the 112 issues fixed in today’s patch batch involve “critical” problems in Windows, or those that can be exploited by malware or malcontents to seize complete, remote control over a vulnerable Windows computer without any help from users.

Most of the rest were assigned the rating “important,” which in Redmond parlance refers to a vulnerability whose exploitation could “compromise the confidentiality, integrity, or availability of user data, or of the integrity or availability of processing resources.”

A chief concern among all these updates this month is CVE-2020-17087, which is an “important” bug in the Windows kernel that is already seeing active exploitation. CVE-2020-17087 is not listed as critical because it’s what’s known as a privilege escalation flaw that would allow an attacker who has already compromised a less powerful user account on a system to gain administrative control. In essence, it would have to be chained with another exploit.

Unfortunately, this is exactly what Google researchers described witnessing recently. On Oct. 20, Google released an update for its Chrome browser which fixed a bug (CVE-2020-15999) that was seen being used in conjunction with CVE-2020-17087 to compromise Windows users.

If you take a look at the advisory Microsoft released today for CVE-2020-17087 (or any others from today’s batch), you might notice they look a bit more sparse. That’s because Microsoft has opted to restructure those advisories around the Common Vulnerability Scoring System (CVSS) format to more closely align the format of the advisories with that of other major software vendors.

But in so doing, Microsoft has also removed some useful information, such as the description explaining in broad terms the scope of the vulnerability, how it can be exploited, and what the result of the exploitation might be. Microsoft explained its reasoning behind this shift in a blog post.

Not everyone is happy with the new format. Bob Huber, chief security officer at Tenable, praised Microsoft for adopting an industry standard, but said the company should consider that folks who review Patch Tuesday releases aren’t security practitioners but rather IT counterparts responsible for actually applying the updates who often aren’t able (and shouldn’t have to) decipher raw CVSS data.

“With this new format, end users are completely blind to how a particular CVE impacts them,” Huber said. “What’s more, this makes it nearly impossible to determine the urgency of a given patch. It’s difficult to understand the benefits to end-users. However, it’s not too difficult to see how this new format benefits bad actors. They’ll reverse engineer the patches and, by Microsoft not being explicit about vulnerability details, the advantage goes to attackers, not defenders. Without the proper context for these CVEs, it becomes increasingly difficult for defenders to prioritize their remediation efforts.”

Dustin Childs with Trend Micro‘s Zero Day Initiative also puzzled over the lack of details included in Microsoft advisories tied to two other flaws fixed today — including one in Microsoft Exchange Server (CVE-2020-16875) and CVE-2020-17051, which is a scary-looking weakness in the Windows Network File System (NFS).

The Exchange problem, Childs said, was reported by the winner of the Pwn2Own Miami bug finding contest.

“With no details provided by Microsoft, we can only assume this is the bypass of CVE-2020-16875 he had previously mentioned,” Childs said. “It is very likely he will publish the details of these bugs soon. Microsoft rates this as important, but I would treat it as critical, especially since people seem to find it hard to patch Exchange at all.”

Likewise, with CVE-2020-17051, there was a noticeable lack of detail for bug that earned a CVSS score of 9.8 (10 is the most dangerous).

“With no description to work from, we need to rely on the CVSS to provide clues about the real risk from the bug,” Childs said. “Consider this is listed as no user interaction with low attack complexity, and considering NFS is a network service, you should treat this as wormable until we learn otherwise.”

Separately, Adobe today released updates to plug at least 14 security holes in Adobe Acrobat and Reader. Details about those fixes are available here. There are no security updates for Adobe’s Flash Player, which Adobe has said will be retired at the end of the year. Microsoft, which has bundled versions of Flash with its Web browsers, says it plans to ship an update in December that will remove Flash from Windows PCs, and last month it made the removal tool available for download.

Windows 10 users should be aware that the operating system will download updates and install them on its own schedule, closing out active programs and rebooting the system. If you wish to ensure Windows has been set to pause updating so you can back up your files and/or system, see this guide.

But please do back up your system before applying any of these updates. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.

Microsoft Patch Tuesday, Sept. 2020 Edition

Microsoft today released updates to remedy nearly 130 security vulnerabilities in its Windows operating system and supported software. None of the flaws are known to be currently under active exploitation, but 23 of them could be exploited by malware or malcontents to seize complete control of Windows computers with little or no help from users.

The majority of the most dangerous or “critical” bugs deal with issues in Microsoft’s various Windows operating systems and its web browsers, Internet Explorer and Edge. September marks the seventh month in a row Microsoft has shipped fixes for more than 100 flaws in its products, and the fourth month in a row that it fixed more than 120.

Among the chief concerns for enterprises this month is CVE-2020-16875, which involves a critical flaw in the email software Microsoft Exchange Server 2016 and 2019. An attacker could leverage the Exchange bug to run code of his choosing just by sending a booby-trapped email to a vulnerable Exchange server.

“That doesn’t quite make it wormable, but it’s about the worst-case scenario for Exchange servers,” said Dustin Childs, of Trend Micro’s Zero Day Initiative. “We have seen the previously patched Exchange bug CVE-2020-0688 used in the wild, and that requires authentication. We’ll likely see this one in the wild soon. This should be your top priority.”

Also not great for companies to have around is CVE-2020-1210, which is a remote code execution flaw in supported versions of Microsoft Sharepoint document management software that bad guys could attack by uploading a file to a vulnerable Sharepoint site. Security firm Tenable notes that this bug is reminiscent of CVE-2019-0604, another Sharepoint problem that’s been exploited for cybercriminal gains since April 2019.

Microsoft fixed at least five other serious bugs in Sharepoint versions 2010 through 2019 that also could be used to compromise systems running this software. And because ransomware purveyors have a history of seizing upon Sharepoint flaws to wreak havoc inside enterprises, companies should definitely prioritize deployment of these fixes, says Alan Liska, senior security architect at Recorded Future.

Todd Schell at Ivanti reminds us that Patch Tuesday isn’t just about Windows updates: Google has shipped a critical update for its Chrome browser that resolves at least five security flaws that are rated high severity. If you use Chrome and notice an icon featuring a small upward-facing arrow inside of a circle to the right of the address bar, it’s time to update. Completely closing out Chrome and restarting it should apply the pending updates.

Once again, there are no security updates available today for Adobe’s Flash Player, although the company did ship a non-security software update for the browser plugin. The last time Flash got a security update was June 2020, which may suggest researchers and/or attackers have stopped looking for flaws in it. Adobe says it will retire the plugin at the end of this year, and Microsoft has said it plans to completely remove the program from all Microsoft browsers via Windows Update by then.

Before you update with this month’s patch batch, please make sure you have backed up your system and/or important files. It’s not uncommon for Windows updates to hose one’s system or prevent it from booting properly, and some updates even have known to erase or corrupt files.

So do yourself a favor and backup before installing any patches. Windows 10 even has some built-in tools to help you do that, either on a per-file/folder basis or by making a complete and bootable copy of your hard drive all at once.

And if you wish to ensure Windows has been set to pause updating so you can back up your files and/or system before the operating system decides to reboot and install patches on its own schedule, see this guide.

As always, if you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a better-than-even chance other readers have experienced the same and may chime in here with some helpful tips.

Why & Where You Should You Plant Your Flag

Several stories here have highlighted the importance of creating accounts online tied to your various identity, financial and communications services before identity thieves do it for you. This post examines some of the key places where everyone should plant their virtual flags.

As KrebsOnSecurity observed back in 2018, many people — particularly older folks — proudly declare they avoid using the Web to manage various accounts tied to their personal and financial data — including everything from utilities and mobile phones to retirement benefits and online banking services. From that story:

“The reasoning behind this strategy is as simple as it is alluring: What’s not put online can’t be hacked. But increasingly, adherents to this mantra are finding out the hard way that if you don’t plant your flag online, fraudsters and identity thieves may do it for you.”

“The crux of the problem is that while most types of customer accounts these days can be managed online, the process of tying one’s account number to a specific email address and/or mobile device typically involves supplying personal data that can easily be found or purchased online — such as Social Security numbers, birthdays and addresses.”

In short, although you may not be required to create online accounts to manage your affairs at your ISP, the U.S. Postal Service, the credit bureaus or the Social Security Administration, it’s a good idea to do so for several reasons.

Most importantly, the majority of the entities I’ll discuss here allow just one registrant per person/customer. Thus, even if you have no intention of using that account, establishing one will be far easier than trying to dislodge an impostor who gets there first using your identity data and an email address they control.

Also, the cost of planting your flag is virtually nil apart from your investment of time. In contrast, failing to plant one’s flag can allow ne’er-do-wells to create a great deal of mischief for you, whether it be misdirecting your service or benefits elsewhere, or canceling them altogether.

Before we dive into the list, a couple of important caveats. Adding multi-factor authentication (MFA) at these various providers (where available) and/or establishing a customer-specific personal identification number (PIN) also can help secure online access. For those who can’t be convinced to use a password manager, even writing down all of the account details and passwords on a slip of paper can be helpful, provided the document is secured in a safe place.

Perhaps the most important place to enable MFA is with your email accounts. Armed with access to your inbox, thieves can then reset the password for any other service or account that is tied to that email address.

People who don’t take advantage of these added safeguards may find it far more difficult to regain access when their account gets hacked, because increasingly thieves will enable multi-factor options and tie the account to a device they control.

Secondly, guard the security of your mobile phone account as best you can (doing so might just save your life). The passwords for countless online services can be reset merely by entering a one-time code sent via text message to the phone number on file for the customer’s account.

And thanks to the increasing prevalence of a crime known as SIM swapping, thieves may be able to upend your personal and financial life simply by tricking someone at your mobile service provider into diverting your calls and texts to a device they control.

Most mobile providers offer customers the option of placing a PIN or secret passphrase on their accounts to lessen the likelihood of such attacks succeeding, but these protections also usually fail when the attackers are social engineering some $12-an-hour employee at a mobile phone store.

Your best option is to reduce your overall reliance on your phone number for added authentication at any online service. Many sites now offer MFA options that are app-based and not tied to your mobile service, and this is your best option for MFA wherever possible.

YOUR CREDIT FILES

First and foremost, all U.S. residents should ensure they have accounts set up online at the three major credit bureaus — Equifax, Experian and Trans Union.

It’s important to remember that the questions these bureaus will ask to verify your identity are not terribly difficult for thieves to answer or guess just by referencing public records and/or perhaps your postings on social media.

You will need accounts at these bureaus if you wish to freeze your credit file. KrebsOnSecurity has for many years urged all readers to do just that, because freezing your file is the best way to prevent identity thieves from opening new lines of credit in your name. Parents and guardians also can now freeze the files of their dependents for free.

For more on what a freeze entails and how to place or thaw one, please see this post. Beyond the big three bureaus, Innovis is a distant fourth bureau that some entities use to check consumer creditworthiness. Fortunately, filing a freeze with Innovis likewise is free and relatively painless.

It’s also a good idea to notify a company called ChexSystems to keep an eye out for fraud committed in your name. Thousands of banks rely on ChexSystems to verify customers who are requesting new checking and savings accounts, and ChexSystems lets consumers place a security alert on their credit data to make it more difficult for ID thieves to fraudulently obtain checking and savings accounts. For more information on doing that with ChexSystems, see this link.

If you placed a freeze on your file at the major bureaus more than a few years ago but haven’t revisited the bureaus’ sites lately, it might be wise to do that soon. Following its epic 2017 data breach, Equifax reconfigured its systems to invalidate the freeze PINs it previously relied upon to unfreeze a file, effectively allowing anyone to bypass that PIN if they can glean a few personal details about you. Experian’s site also has undermined the security of the freeze PIN.

I mentioned planting your flag at the credit bureaus first because if you plan to freeze your credit files, it may be wise to do so after you have planted your flag at all the other places listed in this story. That’s because these other places may try to check your identity records at one or more of the bureaus, and having a freeze in place may interfere with that account creation.

YOUR FINANCIAL INSTITUTIONS

I can’t tell you how many times people have proudly told me they don’t bank online, and prefer to manage all of their accounts the old fashioned way. I always respond that while this is totally okay, you still need to establish an online account for your financial providers because if you don’t someone may do it for you.

This goes doubly for any retirement and pension plans you may have. It’s a good idea for people with older relatives to help those individuals set up and manage online identities for their various accounts — even if those relatives never intend to access any of the accounts online.

This process is doubly important for parents and relatives who have just lost a spouse. When someone passes away, there’s often an obituary in the paper that offers a great deal of information about the deceased and any surviving family members, and identity thieves love to mine this information.

YOUR GOVERNMENT

Whether you’re approaching retirement, middle-aged or just starting out in your career, you should establish an account online at the U.S. Social Security Administration. Maybe you don’t believe Social Security money will actually still be there when you retire, but chances are you’re nevertheless paying into the system now. Either way, the plant-your-flag rules still apply.

Ditto for the Internal Revenue Service. A few years back, ID thieves who specialize in perpetrating tax refund fraud were massively registering people at the IRS’s website to download key data from their prior years’ tax transcripts. While the IRS has improved its taxpayer validation and security measures since then, it’s a good idea to mark your territory here as well.

The same goes for your state’s Department of Motor Vehicles (DMV), which maintains an alarming amount of information about you whether you have an online account there or not. Because the DMV also is the place that typically issues state drivers licenses, you really don’t want to mess around with the possibility that someone could register as you, change your physical address on file, and obtain a new license in your name.

Last but certainly not least, you should create an account for your household at the U.S. Postal Service’s Web site. Having someone divert your mail or delay delivery of it for however long they like is not a fun experience.

Also, the USPS has this nifty service called Informed Delivery, which lets residents view scanned images of all incoming mail prior to delivery. In 2018, the U.S. Secret Service warned that identity thieves have been abusing Informed Delivery to let them know when residents are about to receive credit cards or notices of new lines of credit opened in their names. Do yourself a favor and create an Informed Delivery account as well. Note that multiple occupants of the same street address can each have their own accounts.

YOUR HOME

Online accounts coupled with the strongest multi-factor authentication available also are important for any services that provide you with telephone, television and Internet access.

Strange as it may sound, plenty of people who receive all of these services in a bundle from one ISP do not have accounts online to manage their service. This is dangerous because if thieves can establish an account on your behalf, they can then divert calls intended for you to their own phones.

My original Plant Your Flag piece in 2018 told the story of an older Florida man who had pricey jewelry bought in his name after fraudsters created an online account at his ISP and diverted calls to his home phone number so they could intercept calls from his bank seeking to verify the transactions.

If you own a home, chances are you also have an account at one or more local utility providers, such as power and water companies. If you don’t already have an account at these places, create one and secure access to it with a strong password and any other access controls available.

These frequently monopolistic companies traditionally have poor to non-existent fraud controls, even though they effectively operate as mini credit bureaus. Bear in mind that possession of one or more of your utility bills is often sufficient documentation to establish proof of identity. As a result, such records are highly sought-after by identity thieves.

Another common way that ID thieves establish new lines of credit is by opening a mobile phone account in a target’s name. A little-known entity that many mobile providers turn to for validating new mobile accounts is the National Consumer Telecommunications and Utilities Exchange, or nctue.com. Happily, the NCTUE allows consumers to place a freeze on their file by calling their 800-number, 1-866-349-5355. For more information on the NCTUE, see this page.

Have I missed any important items? Please sound off in the comments below.