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Patch Tuesday, October 2021 Edition

mardi 12 octobre 2021 à 21:52

Microsoft today issued updates to plug more than 70 security holes in its Windows operating systems and other software, including one vulnerability that is already being exploited. This month’s Patch Tuesday also includes security fixes for the newly released Windows 11 operating system. Separately, Apple has released updates for iOS and iPadOS to address a flaw that is being actively attacked.

Firstly, Apple has released iOS 15.0.2 and iPadOS 15.0.2 to fix a zero-day vulnerability (CVE-2021-30883) that is being leveraged in active attacks targeting iPhone and iPad users. Lawrence Abrams of Bleeping Computer writes that the flaw could be used to steal data or install malware, and that soon after Apple patched the bug security researcher Saar Amar published a technical writeup and proof-of-concept exploit that was derived from reverse engineering Apple’s patch.

Abrams said the list of impacted Apple devices is quite extensive, affecting older and newer models. If you own an iPad or iPhone — or any other Apple device — please make sure it’s up to date with the latest security patches.

Three of the weaknesses Microsoft addressed today tackle vulnerabilities rated “critical,” meaning that malware or miscreants could exploit them to gain complete, remote control over vulnerable systems — with little or no help from targets.

One of the critical bugs concerns Microsoft Word, and two others are remote code execution flaws in Windows Hyper-V, the virtualization component built into Windows. CVE-2021-38672 affects Windows 11 and Windows Server 2022; CVE-2021-40461 impacts both Windows 11 and Windows 10 systems, as well as Server versions.

But as usual, some of the more concerning security weaknesses addressed this month earned Microsoft’s slightly less dire “important” designation, which applies to a vulnerability “whose exploitation could result in compromise of the confidentiality, integrity, or availability of user data, or of the integrity or availability of processing resources.”

The flaw that’s under active assault — CVE-2021-40449 — is an important “elevation of privilege” vulnerability, meaning it can be leveraged in combination with another vulnerability to let attackers run code of their choice as administrator on a vulnerable system.

CVE-2021-36970 is an important spoofing vulnerability in Microsoft’s Windows Print Spooler. The flaw was discovered by the same researchers credited with the discovery of one of two vulnerabilities that became known as PrintNightmare — the widespread exploitation of a critical Print Spooler flaw that forced Microsoft to issue an emergency security update back in July. Microsoft assesses CVE-2021-36970 as “exploitation more likely.”

“While no details have been shared publicly about the flaw, this is definitely one to watch for, as we saw a constant stream of Print Spooler-related vulnerabilities patched over the summer while ransomware groups began incorporating PrintNightmare into their affiliate playbook,” said Satnam Narang, staff research engineer at Tenable. “We strongly encourage organizations to apply these patches as soon as possible.”

CVE-2021-26427 is another important bug in Microsoft Exchange Server, which has been under siege lately from attackers. In March, threat actors pounced on four separate zero-day flaws in Exchange that allowed them to siphon email from and install backdoors at hundreds of thousands of organizations.

This month’s Exchange bug earned a CVSS score of 9.0 (10 is the most dangerous). Kevin Breen of Immersive Labs points out that Microsoft has marked this flaw as less likely to be exploited, probably because an attacker would already need access to your network before using the vulnerability.

“Email servers will always be prime targets, simply due to the amount of data contained in emails and the range of possible ways attackers could use them for malicious purposes. While it’s not right at the top of my list of priorities to patch, it’s certainly one to be wary of.”

Also today, Adobe issued security updates for a range of products, including Adobe Reader and Acrobat, Adobe Commerce, and Adobe Connect.

For a complete rundown of all patches released today and indexed by severity, check out the always-useful Patch Tuesday roundup from the SANS Internet Storm Center, and the Patch Tuesday data put together by Morphus Labs. And it’s not a bad idea to hold off updating for a few days until Microsoft works out any kinks in the updates: AskWoody.com frequently has the lowdown on any patches that are causing problems for Windows users.

On that note, 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.

If you experience glitches or problems installing any of these patches this month, please consider leaving a comment about it below; there’s a decent chance other readers have experienced the same and may chime in here with useful tips.

What Happened to Facebook, Instagram, & WhatsApp?

lundi 4 octobre 2021 à 21:05

Facebook and its sister properties Instagram and WhatsApp are suffering from ongoing, global outages. We don’t yet know why this happened, but the how is clear: Earlier this morning, something inside Facebook caused the company to revoke key digital records that tell computers and other Internet-enabled devices how to find these destinations online.

Kentik’s view of the Facebook, Instagram and WhatsApp outage.

Doug Madory is director of internet analysis at Kentik, a San Francisco-based network monitoring company. Madory said at approximately 11:39 a.m. ET today (15:39 UTC), someone at Facebook caused an update to be made to the company’s Border Gateway Protocol (BGP) records. BGP is a mechanism by which Internet service providers of the world share information about which providers are responsible for routing Internet traffic to which specific groups of Internet addresses.

In simpler terms, sometime this morning Facebook took away the map telling the world’s computers how to find its various online properties. As a result, when one types Facebook.com into a web browser, the browser has no idea where to find Facebook.com, and so returns an error page.

In addition to stranding billions of users, the Facebook outage also has stranded its employees from communicating with one another using their internal Facebook tools. That’s because Facebook’s email and tools are all managed in house and via the same domains that are now stranded.

“Not only are Facebook’s services and apps down for the public, its internal tools and communications platforms, including Workplace, are out as well,” New York Times tech reporter Ryan Mac tweeted. “No one can do any work. Several people I’ve talked to said this is the equivalent of a ‘snow day’ at the company.”

The mass outage comes just hours after CBS’s 60 Minutes aired a much-anticipated interview with Frances Haugen, the Facebook whistleblower who recently leaked a number of internal Facebook investigations showing the company knew its products were causing mass harm, and that it prioritized profits over taking bolder steps to curtail abuse on its platform — including disinformation and hate speech.

We don’t know how or why the outages persist at Facebook and its other properties, but the changes had to have come from inside the company, as Facebook manages those records internally. Whether the changes were made maliciously or by accident is anyone’s guess at this point.

Madory said it could be that someone at Facebook just screwed up.

“In the past year or so, we’ve seen a lot of these big outages where they had some sort of update to their global network configuration that went awry,” Madory said. “We obviously can’t rule out someone hacking them, but they also could have done this to themselves.”

In the meantime, several different domain registration companies listed the domain Facebook.com as up for sale. There’s no reason to believe this domain will actually be sold as a result, but it’s fun to consider how many billions of dollars this domain could fetch on the open market.

This is a developing story and will likely be updated throughout the day.

FCC Proposal Targets SIM Swapping, Port-Out Fraud

vendredi 1 octobre 2021 à 17:09

The U.S. Federal Communications Commission (FCC) is asking for feedback on new proposed rules to crack down on SIM swapping and number port-out fraud, increasingly prevalent scams in which identity thieves hijack a target’s mobile phone number and use that to wrest control over the victim’s online identity.

In a long-overdue notice issued Sept. 30, the FCC said it plans to move quickly on requiring the mobile companies to adopt more secure methods of authenticating customers before redirecting their phone number to a new device or carrier.

“We have received numerous complaints from consumers who have suffered significant distress, inconvenience, and financial harm as a result of SIM swapping and port-out fraud,” the FCC wrote. “Because of the serious harms associated with SIM swap fraud, we believe that a speedy implementation is appropriate.”

The FCC said the proposal was in response to a flood of complaints to the agency and the U.S. Federal Trade Commission (FTC) about fraudulent SIM swapping and number port-out fraud. SIM swapping happens when the fraudsters trick or bribe an employee at a mobile phone store into transferring control of a target’s phone number to a device they control.

From there, the attackers can reset the password for almost any online account tied to that mobile number, because most online services still allow people to reset their passwords simply by clicking a link sent via SMS to the phone number on file.

Scammers commit number port-out fraud by posing as the target and requesting that their number be transferred to a different mobile provider (and to a device the attackers control).

The FCC said the carriers have traditionally sought to address both forms of phone number fraud by requiring static data about the customer that is no longer secret and has been exposed in a variety of places already — such as date of birth and Social Security number. By way of example, the commission pointed to the recent breach at T-Mobile that exposed this data on 40 million current, past and prospective customers.

What’s more, victims of SIM swapping and number port-out fraud are often the last to know about their victimization. The FCC said it plans to prohibit wireless carriers from allowing a SIM swap unless the carrier uses a secure method of authenticating its customer. Specifically, the commission proposes that carriers be required to verify a “pre-established password” with customers before making any changes to their accounts.

According to the FCC, several examples of pre-established passwords include:

-a one-time passcode sent via text message to the account phone number or a pre-registered backup number
-a one-time passcode sent via email to the email address associated with the account
-a passcode sent using a voice call to the account phone number or pre-registered back-up telephone number.

The commission said it was also considering updating its rules to require wireless carriers to develop procedures for responding to failed authentication attempts and to notify customers immediately of any requests for SIM changes.

Additionally, the FCC said it may impose additional customer service, training, and transparency requirements for the carriers, noting that too many customer service personnel at the wireless carriers lack training on how to assist customers who’ve had their phone numbers stolen.

The FCC said some of the consumer complaints it has received “describe wireless carrier customer service representatives and store employees who do not know how to address instances of fraudulent SIM swaps or port-outs, resulting in customers spending many hours on the phone and at retail stores trying to get resolution. Other consumers complain that their wireless carriers have refused to provide them with documentation related to the fraudulent SIM swaps, making it difficult for them to pursue claims with their financial institutions or law enforcement.”

“Several consumer complaints filed with the Commission allege that the wireless carrier’s store employees are involved in the fraud, or that carriers completed SIM swaps despite the customer having previously set a PIN or password on the account,” the commission continued.

Allison Nixon, an expert on SIM swapping attacks chief research officer with New York City-based cyber intelligence firm Unit221B, said any new authentication requirements will have to balance the legitimate use cases for customers requesting a new SIM card when their device is lost or stolen. A SIM card is the small, removable smart card that associates a mobile device to its carrier and phone number.

“Ultimately, any sort of static defense is only going to work in the short term,” Nixon said. “The use of SMS as a 2nd factor in itself is a static defense. And the criminals adapted and made the problem actually worse than the original problem it was designed to solve. The long term solution is that the system needs to be responsive to novel fraud schemes and adapt to it faster than the speed of legislation.”

Eager to weigh in on the FCC’s proposal? They want to hear from you. The electronic comment filing system is here, and the docket number for this proceeding is WC Docket No. 21-341.

The Rise of One-Time Password Interception Bots

mercredi 29 septembre 2021 à 14:22

In February, KrebsOnSecurity wrote about a novel cybercrime service that helped attackers intercept the one-time passwords (OTPs) that many websites require as a second authentication factor in addition to passwords. That service quickly went offline, but new research reveals a number of competitors have since launched bot-based services that make it relatively easy for crooks to phish OTPs from targets.

An ad for the OTP interception service/bot “SMSRanger.”

Many websites now require users to supply both a password and a numeric code/OTP token sent via text message, or one generated by mobile apps like Authy and Google Authenticator. The idea is that even if the user’s password gets stolen, the attacker still can’t access the user’s account without that second factor — i.e. without access to the victim’s mobile device or phone number.

The OTP interception service featured earlier this year Otp[.]agency — advertised a web-based bot designed to trick targets into giving up OTP tokens. The customer would enter a target’s phone number and name, and OTP Agency would initiate an automated phone call that alerts that person about unauthorized activity on their account.

The call would prompt the target to enter an OTP token generated by their phone’s mobile app (“for authentication purposes”), and that code would then get relayed back to the bad guy customers’ panel at the OTP Agency website.

OTP Agency took itself offline within hours of that story. But according to research from cyber intelligence firm Intel 471, multiple new OTP interception services have emerged to fill that void. And all of them operate via Telegram, a cloud-based instant messaging system.

“Intel 471 has seen an uptick in services on the cybercrime underground that allow attackers to intercept one-time password (OTP) tokens,” the company wrote in a blog post today. “Over the past few months, we’ve seen actors provide access to services that call victims, appear as a legitimate call from a specific bank and deceive victims into typing an OTP or other verification code into a mobile phone in order to capture and deliver the codes to the operator. Some services also target other popular social media platforms or financial services, providing email phishing and SIM swapping capabilities.”

Intel471 says one new Telegram OTP bot called “SMSRanger” is popular because it’s remarkably easy to use, and probably because of the many testimonials posted by customers who seem happy with its frequent rate of success in extracting OTP tokens when the attacker already has the target’s “fullz,” personal information such as Social Security number and date of birth. From their analysis:

“Those who pay for access can use the bot by entering commands similar to how bots are used on popular workforce collaboration tool Slack. A simple slash command allows a user to enable various ‘modes’ — scripts aimed as various services — that can target specific banks, as well as PayPal, Apple Pay, Google Pay, or a wireless carrier.

Once a target’s phone number has been entered, the bot does the rest of the work, ultimately granting access to whatever account has been targeted. Users claim that SMSRanger has an efficacy rate of about 80% if the victim answered the call and the full information (fullz) the user provided was accurate and updated.”

Another OTP interception service called SMS Buster requires a tad more effort from a customer, Intel 471 explains:

“The bot provides options to disguise a call to make it appear as a legitimate contact from a specific bank while letting the attackers choose to dial from any phone number. From there, an attacker could follow a script to trick a victim into providing sensitive details such as an ATM personal identification number (PIN), card verification value (CVV) and OTP, which could then be sent to an individual’s Telegram account. The bot, which was used by attackers targeting Canadian victims, gives users the chance to launch attacks in French and English.” 

These services are springing up because they work and they’re profitable. And they’re profitable because far too many websites and services funnel users toward multi-factor authentication methods that can be intercepted, spoofed, or misdirected — like SMS-based one-time codes, or even app-generated OTP tokens.

The idea behind true “two-factor authentication” is that the user is required to present two out of three of the following: Something they have (mobile devices); something they know (passwords); or something they are (biometrics). For example, you present your credentials to a website, and the site prompts you to approve the login via a prompt that pops up on your registered mobile device. That is true two-factor authentication: Something you have, and something you know (and maybe also even something you are).

The 2fa SMS Buster bot on Telegram. Image: Intel 471.

In addition, these so-called “push notification” methods include important time-based contexts that add security: They happen directly after the user submits their credentials; and the opportunity to approve the push notification expires after a short period.

But in so many instances, what sites request is basically two things you know (a password and a one-time code) to be submitted through the same channel (a web browser). This is usually still better than no multi-factor authentication at all, but as these services show there are now plenty of options of circumventing this protection.

I hope these OTP interception services make clear that you should never provide any information in response to an unsolicited phone call. It doesn’t matter who claims to be calling: If you didn’t initiate the contact, hang up. Don’t put them on hold while you call your bank; the scammers can get around that, too. Just hang up. Then you can call your bank or whoever else you need.

Unfortunately, those most likely to fall for these OTP interception schemes are people who are less experienced with technology. If you’re the resident or family IT geek and have the ability to update or improve the multi-factor authentication profiles for your less tech-savvy friends and loved ones, that would be a fabulous way to show you care — and to help them head off a potential disaster at the hands of one of these bot services.

When was the last time you reviewed your multi-factor settings and options at the various websites entrusted with your most precious personal and financial information? It might be worth paying a visit to 2fa.directory (formerly twofactorauth[.]org) for a checkup.

Apple AirTag Bug Enables ‘Good Samaritan’ Attack

mardi 28 septembre 2021 à 17:49

The new $30 AirTag tracking device from Apple has a feature that allows anyone who finds one of these tiny location beacons to scan it with a mobile phone and discover its owner’s phone number if the AirTag has been set to lost mode. But according to new research, this same feature can be abused to redirect the Good Samaritan to an iCloud phishing page — or to any other malicious website.

The AirTag’s “Lost Mode” lets users alert Apple when an AirTag is missing. Setting it to Lost Mode generates a unique URL at https://found.apple.com, and allows the user to enter a personal message and contact phone number. Anyone who finds the AirTag and scans it with an Apple or Android phone will immediately see that unique Apple URL with the owner’s message.

When scanned, an AirTag in Lost Mode will present a short message asking the finder to call the owner at at their specified phone number. This information pops up without asking the finder to log in or provide any personal information. But your average Good Samaritan might not know this.

That’s important because Apple’s Lost Mode doesn’t currently stop users from injecting arbitrary computer code into its phone number field — such as code that causes the Good Samaritan’s device to visit a phony Apple iCloud login page.

A sample “Lost Mode” message. Image: Medium @bobbyrsec

The vulnerability was discovered and reported to Apple by Bobby Rauch, a security consultant and penetration tester based in Boston. Rauch told KrebsOnSecurity the AirTag weakness makes the devices cheap and possibly very effective physical trojan horses.

“I can’t remember another instance where these sort of small consumer-grade tracking devices at a low cost like this could be weaponized,” Rauch said.

Consider the scenario where an attacker drops a malware-laden USB flash drive in the parking lot of a company he wants to hack into. Odds are that sooner or later some employee is going to pick that sucker up and plug it into a computer — just to see what’s on it (the drive might even be labeled something tantalizing, like “Employee Salaries”).

If this sounds like a script from a James Bond movie, you’re not far off the mark. A USB stick with malware is very likely how U.S. and Israeli cyber hackers got the infamous Stuxnet worm into the internal, air-gapped network that powered Iran’s nuclear enrichment facilities a decade ago. In 2008, a cyber attack described at the time as “the worst breach of U.S. military computers in history” was traced back to a USB flash drive left in the parking lot of a U.S. Department of Defense facility.

In the modern telling of this caper, a weaponized AirTag tracking device could be used to redirect the Good Samaritan to a phishing page, or to a website that tries to foist malicious software onto her device.

Rauch contacted Apple about the bug on June 20, but for three months when he inquired about it the company would say only that it was still investigating. Last Thursday, the company sent Rauch a follow-up email stating they planned to address the weakness in an upcoming update, and in the meantime would he mind not talking about it publicly?

Rauch said Apple never acknowledged basic questions he asked about the bug, such as if they had a timeline for fixing it, and if so whether they planned to credit him in the accompanying security advisory. Or whether his submission would qualify for Apple’s “bug bounty” program, which promises financial rewards of up to $1 million for security researchers who report security bugs in Apple products.

Rauch said he’s reported many software vulnerabilities to other vendors over the years, and that Apple’s lack of communication prompted him to go public with his findings — even though Apple says staying quiet about a bug until it is fixed is how researchers qualify for recognition in security advisories.

“I told them, ‘I’m willing to work with you if you can provide some details of when you plan on remediating this, and whether there would be any recognition or bug bounty payout’,” Rauch said, noting that he told Apple he planned to publish his findings within 90 days of notifying them. “Their response was basically, ‘We’d appreciate it if you didn’t leak this.'”

Rauch’s experience echoes that of other researchers interviewed in a recent Washington Post article about how not fun it can be to report security vulnerabilities to Apple, a notoriously secretive company. The common complaints were that Apple is slow to fix bugs and doesn’t always pay or publicly recognize hackers for their reports, and that researchers often receive little or no feedback from the company.

The risk, of course, is that some researchers may decide it’s less of a hassle to sell their exploits to vulnerability brokers, or on the darknet — both of which often pay far more than bug bounty awards.

There’s also a risk that frustrated researchers will simply post their findings online for everyone to see and exploit — regardless of whether the vendor has released a patch. Earlier this week, a security researcher who goes by the handle “illusionofchaos” released writeups on three zero-day vulnerabilities in Apple’s iOS mobile operating system — apparently out of frustration over trying to work with Apple’s bug bounty program.

Ars Technica reports that on July 19 Apple fixed a bug that llusionofchaos reported on April 29, but that Apple neglected to credit him in its security advisory.

“Frustration with this failure of Apple to live up to its own promises led illusionofchaos to first threaten, then publicly drop this week’s three zero-days,” wrote Jim Salter for Ars. “In illusionofchaos’ own words: ‘Ten days ago I asked for an explanation and warned then that I would make my research public if I don’t receive an explanation. My request was ignored so I’m doing what I said I would.'”

Rauch said he realizes the AirTag bug he found probably isn’t the most pressing security or privacy issue Apple is grappling with at the moment. But he said neither is it difficult to fix this particular flaw, which requires additional restrictions on data that AirTag users can enter into the Lost Mode’s phone number settings.

“It’s a pretty easy thing to fix,” he said. “Having said that, I imagine they probably want to also figure out how this was missed in the first place.”

Apple has not responded to requests for comment.

Update, 12:31: Rauch shared an email showing Apple communicated their intention to fix the bug just hours before — not after — KrebsOnSecurity reached out to them for comment. The story above has been changed to reflect that.