Microsoft today released updates to plug 50 security holes in various flavors of Windows and related software. The patch batch includes a fix for a flaw in Windows 10 and server equivalents of this operating system that prompted an unprecedented public warning from the U.S. National Security Agency. This month also marks the end of mainstream support for Windows 7, a still broadly-used operating system that will no longer be supplied with security updates.
As first reported Monday by KrebsOnSecurity, Microsoft addressed a severe bug (CVE-2020-0601) in Windows 10 and Windows Server 2016/19 reported by the NSA that allows an attacker to spoof the digital signature tied to a specific piece of software. Such a weakness could be abused by attackers to make malware appear to be a benign program that was produced and signed by a legitimate software company.
An advisory (PDF) released today by the NSA says the flaw may have far more wide-ranging security implications, noting that the “exploitation of the vulnerability allows attackers to defeat trusted network connections and deliver executable code while appearing as legitimately trusted entities.”
“NSA assesses the vulnerability to be severe and that sophisticated cyber actors will understand the underlying flaw very quickly and, if exploited, would render the previously mentioned platforms as fundamentally vulnerable,” the advisory continues. “The consequences of not patching the vulnerability are severe and widespread.”
Matthew Green, an associate professor in the computer science department at Johns Hopkins University, said the flaw involves an apparent implementation weakness in a component of recent Windows versions responsible for validating the legitimacy of authentication requests for a panoply of security functions in the operating system.
Green said attackers can use this weakness to impersonate everything from trusted Web sites to the source of software updates for Windows and other programs.
“Imagine if I wanted to pick the lock in your front door,” Green analogized. “It might be hard for me to come up with a key that will open your door, but what if I could tamper with or present both the key and the lock at the same time?”
Kenneth White, security principal at the software company MongoDB, equated the vulnerability to a phone call that gets routed to a party you didn’t intend to reach.
“You pick up the phone, dial a number and assume you’re talking to your bank or Microsoft or whomever, but the part of the software that confirms who you’re talking to is flawed,” White said. “That’s pretty bad, especially when your system is saying download this piece of software or patch automatically and it’s being done in the background.”
Both Green and White said it likely will be a matter of hours or days before security researchers and/or bad guys work out ways to exploit this bug, given the stakes involved. Indeed, already this evening KrebsOnSecurity has seen indications that people are teasing out such methods, which will likely be posted publicly online soon.
According to security vendor Qualys, only eight of the 50 flaws fixed in today’s patch roundup from Microsoft earned the company’s most dire “critical” rating, a designation reserved for bugs that can be exploited remotely by malware or miscreants to seize complete control over the target computer without any help from users.
Once again, some of those critical flaws include security weaknesses in the way Windows implements Remote Desktop connections, a feature that allows systems to be accessed, viewed and controlled as if the user was seated directly in front of the remote computer. Other critical patches include updates for the Web browsers and Web scripting engines built into Windows, as well as fixes for ASP.NET and the .NET Framework.
The security fix for the CVE-2020-0601 bug and others detailed in this post will be offered to Windows users as part of a bundle of patches released today by Microsoft. To see whether any updates are available for your Windows computer, go to the Start menu and type “Windows Update,” then let the system scan for any available patches.
Keep in mind that while staying up-to-date on Windows patches is a must, it’s important to make sure you’re updating only after you’ve backed up your important data and files. A reliable backup means you’re not losing your mind when the odd buggy patch causes problems booting the system. So do yourself a favor and backup your files 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.
Today also marks the last month in which Microsoft will ship security updates for Windows 7 home/personal users. I count myself among some 30 percent of Windows users who still like and (ab)use this operating system in one form or another, and am sad that this day has come to pass. But if you rely on this OS for day-to-day use, it’s probably time to think about upgrading to something newer.
That might be a computer with Windows 10. Or maybe you have always wanted that shiny MacOS computer. If cost is a primary motivator and the user you have in mind doesn’t do much with the system other than browsing the Web, perhaps a Chromebook or an older machine with a recent version of Linux is the answer. Whichever system you choose, it’s important to pick one that fits the owner’s needs and provides security updates on an ongoing basis.
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.
Source: KREBS ON SECURITY
Sources tell KrebsOnSecurity that Microsoft Corp. is slated to release a software update on Tuesday to fix an extraordinarily serious security vulnerability in a core cryptographic component present in all versions of Windows. Those sources say Microsoft has quietly shipped a patch for the bug to branches of the U.S. military and to other high-value customers/targets that manage key Internet infrastructure, and that those organizations have been asked to sign agreements preventing them from disclosing details of the flaw prior to Jan. 14, the first Patch Tuesday of 2020.
According to sources, the vulnerability in question resides in a Windows component known as crypt32.dll, a Windows module that Microsoft says handles “certificate and cryptographic messaging functions in the CryptoAPI.” The Microsoft CryptoAPI provides services that enable developers to secure Windows-based applications using cryptography, and includes functionality for encrypting and decrypting data using digital certificates.
A critical vulnerability in this Windows component could have wide-ranging security implications for a number of important Windows functions, including authentication on Windows desktops and servers, the protection of sensitive data handled by Microsoft’s Internet Explorer/Edge browsers, as well as a number of third-party applications and tools.
Equally concerning, a flaw in crypt32.dll might also be abused to spoof the digital signature tied to a specific piece of software. Such a weakness could be exploited by attackers to make malware appear to be a benign program that was produced and signed by a legitimate software company.
This component was introduced into Windows more than 20 years ago — back in Windows NT 4.0. Consequently, all versions of Windows are likely affected (including Windows XP, which is no longer being supported with patches from Microsoft).
Microsoft has not yet responded to requests for comment. However, KrebsOnSecurity has heard rumblings from several sources over the past 48 hours that this Patch Tuesday (tomorrow) will include a doozy of an update that will need to be addressed immediately by all organizations running Windows.
Update 7:49 p.m. ET: Microsoft responded, saying that it does not discuss the details of reported vulnerabilities before an update is available. The company also said it does “not release production-ready updates ahead of regular Update Tuesday schedule. “Through our Security Update Validation Program (SUVP), we release advance versions of our updates for the purpose of validation and interoperability testing in lab environments,” Microsoft said in a written statement. “Participants in this program are contractually disallowed from applying the fix to any system outside of this purpose and may not apply it to production infrastructure.”
Will Dormann, a security researcher who authors many of the vulnerability reports for the CERT Coordination Center (CERT-CC), tweeted today that “people should perhaps pay very close attention to installing tomorrow’s Microsoft Patch Tuesday updates in a timely manner. Even more so than others. I don’t know…just call it a hunch?” Dormann declined to elaborate on that teaser.
It could be that the timing and topic here (cryptography) is nothing more than a coincidence, but KrebsOnSecurity today received a heads up from the U.S. National Security Agency (NSA) stating that NSA’s Director of Cybersecurity Anne Neuberger is slated to host a call on Jan. 14 with the news media that “will provide advanced notification of a current NSA cybersecurity issue.”
The NSA’s public affairs folks did not respond to requests for more information on the nature or purpose of the discussion. The invitation from the agency said only that the call “reflects NSA’s efforts to enhance dialogue with industry partners regarding its work in the cybersecurity domain.”
Stay tuned for tomorrow’s coverage of Patch Tuesday and possibly more information on this particular vulnerability.
Update, Jan. 14, 9:20 a.m. ET: The NSA’s Neuberger said in a media call this morning that the agency did indeed report this vulnerability to Microsoft, and that this was the first time Microsoft will have credited NSA for reporting a security flaw. Neuberger said NSA researchers discovered the bug in their own research, and that Microsoft’s advisory later today will state that Microsoft has seen no active exploitation of it yet.
According to the NSA, the problem exists in Windows 10 and Windows Server 2016. Asked why the NSA was focusing on this particular vulnerability, Neuberger said the concern was that it “makes trust vulnerable.” The agency declined to say when it discovered the flaw, and that it would wait until Microsoft releases a patch for it later today before discussing further details of the vulnerability.
Update, 1:47 p.m. ET: Microsoft has released updates for this flaw (CVE-2020-0601). Their advisory is here. The NSA’s writeup (PDF) includes quite a bit more detail, as does the advisory from CERT.
Source: KREBS ON SECURITY
Anyone searching for a primer on how to spot clever phishing links need look no further than those targeting customers of Apple, whose brand by many measures remains among the most-targeted. Past stories here have examined how scammers working with organized gangs try to phish iCloud credentials from Apple customers who have a mobile device that is lost or stolen. Today’s piece looks at the well-crafted links used in some of these lures.
KrebsOnSecurity heard from a reader in South Africa who recently received a text message stating his lost iPhone X had been found. The message addressed him by name and said he could view the location of his wayward device by visiting the link https://maps-icloud[.]com — which is most definitely not a legitimate Apple or iCloud link and is one of countless spoofing Apple’s “Find My” service for locating lost Apple devices.
While maps-icloud[.]com is not a particularly convincing phishing domain, a review of the Russian server where that domain is hosted reveals a slew of far more persuasive links spoofing Apple’s brand. Almost all of these include encryption certificates (start with “https://) and begin with the subdomains “apple.” or “icloud.” followed by a domain name starting with “com-“.
Here are just a few examples (the phishing links in this post have been hobbled with brackets to keep them from being clickable):
Savvy readers here no doubt already know this, but to find the true domain referenced in a link, look to the right of “http(s)://” until you encounter the first forward slash (/). The domain directly to the left of that first slash is the true destination; anything that precedes the second dot to the left of that first slash is a subdomain and should be ignored for the purposes of determining the true domain name.
For instance, in the case of the imaginary link below, example.com is the true destination, not apple.com:
Of course, any domain can be used as a redirect to any other domain. Case in point: Targets of the phishing domains above who are undecided on whether the link refers to a legitimate Apple site might seek to load the base domain into a Web browser (minus the customization in the remainder of the link after the first forward slash). To assuage such concerns, the phishers in this case will forward anyone visiting those base domains to Apple’s legitimate iCloud login page (icloud.com).
The best advice to sidestep phishing scams is to avoid clicking on links that arrive unbidden in emails, text messages and other mediums. Most phishing scams invoke a temporal element that warns of dire consequences should you fail to respond or act quickly. If you’re unsure whether the message is legitimate, take a deep breath and visit the site or service in question manually — ideally, using a browser bookmark so as to avoid potential typosquatting sites.
Source: KREBS ON SECURITY