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Microsoft Patch Tuesday, December 2022 Edition

mercredi 14 décembre 2022 à 18:01

Microsoft has released its final monthly batch of security updates for 2022, fixing more than four dozen security holes in its various Windows operating systems and related software. The most pressing patches include a zero-day in a Windows feature that tries to flag malicious files from the Web, a critical bug in PowerShell, and a dangerous flaw in Windows 11 systems that was detailed publicly prior to this week’s Patch Tuesday.

The security updates include patches for Azure, Microsoft Edge, Office, SharePoint Server, SysInternals, and the .NET framework. Six of the update bundles earned Microsoft’s most dire “critical” rating, meaning they fix vulnerabilities that malware or malcontents can use to remotely commandeer an unpatched Windows system — with little to no interaction on the part of the user.

The bug already seeing exploitation is CVE-2022-44698, which allows attackers to bypass the Windows SmartScreen security feature. The vulnerability allows attackers to craft documents that won’t get tagged with Microsoft’s “Mark of the Web,” despite being downloaded from untrusted sites.

“This means no Protected View for Microsoft Office documents, making it easier to get users to do sketchy things like execute malicious macros,
said Greg Wiseman, product manager at security firm Rapid7. This is the second Mark of the Web flaw Microsoft has patched in as many months; both were first publicly detailed over the past two months on Twitter by security researcher Will Dormann.

Publicly disclosed (but not actively exploited for now) is CVE-2022-44710, which is an elevation of privilege flaw in the DirectX graphics component of Windows 11.

Another notable critical bug is CVE-2022-41076, a remote code execution flaw in PowerShell — a key component of Windows that makes it easier to automate system tasks and configurations.

Kevin Breen at Immersive Labs said while Microsoft doesn’t share much detail about CVE-2022-41076 apart from the designation ‘Exploitation More Likely,’ they also note that successful exploitation requires an attacker to take additional actions to prepare the target environment.

“What actions are required is not clear; however, we do know that exploitation requires an authenticated user level of access,” Breen said. “This combination suggests that the exploit requires a social engineering element, and would likely be seen in initial infections using attacks like MalDocs or LNK files.”

Speaking of malicious documents, Trend Micro’s Zero Day Initiative highlights CVE-2022-44713, a spoofing vulnerability in Outlook for Mac.

“We don’t often highlight spoofing bugs, but anytime you’re dealing with a spoofing bug in an e-mail client, you should take notice,” ZDI’s Dustin Childs wrote. “This vulnerability could allow an attacker to appear as a trusted user when they should not be. Now combine this with the SmartScreen Mark of the Web bypass and it’s not hard to come up with a scenario where you receive an e-mail that appears to be from your boss with an attachment entitled “Executive_Compensation.xlsx”. There aren’t many who wouldn’t open that file in that scenario.”

Microsoft also released guidance on reports that certain software drivers certified by Microsoft’s Windows Hardware Developer Program were being used maliciously in post-exploitation activity.

Three different companies reported evidence that malicious hackers were using these signed malicious driver files to lay the groundwork for ransomware deployment inside victim organizations. One of those companies, Sophos, published a blog post Tuesday detailing how the activity was tied to the Russian ransomware group Cuba, which has extorted an estimated $60 million from victims since 2019.

Of course, not all scary and pressing security threats are Microsoft-based. Also on Tuesday, Apple released a bevy of security updates to iOS, iPadOS, macOS, tvOS and Safari, including  a patch for a newly discovered zero-day vulnerability that could lead to remote code execution.

Anyone responsible for maintaining Fortinet or Citrix remote access products probably needs to update, as both are dealing with active attacks on just-patched flaws.

For a closer look at the patches released by Microsoft today (indexed by severity and other metrics) check out the always-useful Patch Tuesday roundup from the SANS Internet Storm Center. 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 usually has the lowdown on any patches that may be causing problems for Windows users.

As always, please consider backing up your system or at least your important documents and data before applying system updates. And if you run into any problems with these updates, please drop a note about it here in the comments.

FBI’s Vetted Info Sharing Network ‘InfraGard’ Hacked

mercredi 14 décembre 2022 à 00:54

InfraGard, a program run by the U.S. Federal Bureau of Investigation (FBI) to build cyber and physical threat information sharing partnerships with the private sector, this week saw its database of contact information on more than 80,000 members go up for sale on an English-language cybercrime forum. Meanwhile, the hackers responsible are communicating directly with members through the InfraGard portal online — using a new account under the assumed identity of a financial industry CEO that was vetted by the FBI itself.

On Dec. 10, 2022, the relatively new cybercrime forum Breached featured a bombshell new sales thread: The user database for InfraGard, including names and contact information for tens of thousands of InfraGard members.

The FBI’s InfraGard program is supposed to be a vetted Who’s Who of key people in private sector roles involving both cyber and physical security at companies that manage most of the nation’s critical infrastructures — including drinking water and power utilities, communications and financial services firms, transportation and manufacturing companies, healthcare providers, and nuclear energy firms.

“InfraGard connects critical infrastructure owners, operators, and stakeholders with the FBI to provide education, networking, and information-sharing on security threats and risks,” the FBI’s InfraGard fact sheet reads.

In response to information shared by KrebsOnSecurity, the FBI said it is aware of a potential false account associated with the InfraGard Portal and that it is actively looking into the matter.

“This is an ongoing situation, and we are not able to provide any additional information at this time,” the FBI said in a written statement.

KrebsOnSecurity contacted the seller of the InfraGard database, a Breached forum member who uses the handle “USDoD” and whose avatar is the seal of the U.S. Department of Defense.

USDoD’s InfraGard sales thread on Breached.

USDoD said they gained access to the FBI’s InfraGard system by applying for a new account using the name, Social Security Number, date of birth  and other personal details of a chief executive officer at a company that was highly likely to be granted InfraGard membership.

The CEO in question — currently the head of a major U.S. financial corporation that has a direct impact on the creditworthiness of most Americans — told KrebsOnSecurity they were never contacted by the FBI seeking to vet an InfraGard application.

USDoD told KrebsOnSecurity their phony application was submitted in November in the CEO’s name, and that the application included a contact email address that they controlled — but also the CEO’s real mobile phone number.

“When you register they said that to be approved can take at least three months,” USDoD said. “I wasn’t expected to be approve[d].”

But USDoD said that in early December, their email address in the name of the CEO received a reply saying the application had been approved (see redacted screenshot to the right). While the FBI’s InfraGard system requires multi-factor authentication by default, users can choose between receiving a one-time code via SMS or email.

“If it was only the phone I will be in [a] bad situation,” USDoD said. “Because I used the person[‘s] phone that I’m impersonating.”

USDoD said the InfraGard user data was made easily available via an Application Programming Interface (API) that is built into several key components of the website that help InfraGard members connect and communicate with each other.

USDoD said after their InfraGard membership was approved, they asked a friend to code a script in Python to query that API and retrieve all available InfraGard user data.

“InfraGard is a social media intelligence hub for high profile persons,” USDoD said. “They even got [a] forum to discuss things.”

To prove they still had access to InfraGard as of publication time Tuesday evening, USDoD sent a direct note through InfraGard’s messaging system to an InfraGard member whose personal details were initially published as a teaser on the database sales thread.

That InfraGard member, who is head of security at a major U.S. technology firm, confirmed receipt of USDoD’s message but asked to remain anonymous for this story.

USDoD acknowledged that their $50,000 asking price for the InfraGard database may be a tad high, given that it is a fairly basic list of people who are already very security-conscious. Also, only about half of the user accounts contain an email address, and most of the other database fields — like Social Security Number and Date of Birth — are completely empty.

“I don’t think someone will pay that price, but I have to [price it] a bit higher to [negotiate] the price that I want,” they explained.

While the data exposed by the infiltration at InfraGard may be minimal, the user data might not have been the true end game for the intruders.

USDoD said they were hoping the imposter account would last long enough for them to finish sending direct messages as the CEO to other executives using the InfraGuard messaging portal. USDoD shared the following redacted screenshot from what they claimed was one such message, although they provided no additional context about it.

A screenshot shared by USDoD showing a message thread in the FBI’s InfraGard system.

USDoD said in their sales thread that the guarantor for the transaction would be Pompompurin, the administrator of the cybercrime forum Breached. By purchasing the database through the forum administrator’s escrow service, would-be buyers can theoretically avoid getting ripped off and ensure the transaction will be consummated to the satisfaction of both parties before money exchanges hands.

Pompompurin has been a thorn in the side of the FBI for years. Their Breached forum is widely considered to be the second incarnation of RaidForums, a remarkably similar English-language cybercrime forum shuttered by the U.S. Department of Justice in April. Prior to its infiltration by the FBI, RaidForums sold access to more than 10 billion consumer records stolen in some of the world’s largest data breaches.

In November 2021, KrebsOnSecurity detailed how Pompompurin abused a vulnerability in an FBI online portal designed to share information with state and local law enforcement authorities, and how that access was used to blast out thousands of hoax email messages — all sent from an FBI email and Internet address.

Update, 10:58 p.m. ET: Updated the story after hearing from the financial company CEO whose identity was used to fool the FBI into approving an InfraGard membership. That CEO said they were never contacted by the FBI.

Update, 11:15 p.m. ET: The FBI just confirmed that it is aware of a potential false account associated with the InfraGard portal. The story now includes their full statement.

This is a developing story. Updates will be noted here with timestamps. 

New Ransom Payment Schemes Target Executives, Telemedicine

jeudi 8 décembre 2022 à 19:25

Ransomware groups are constantly devising new methods for infecting victims and convincing them to pay up, but a couple of strategies tested recently seem especially devious. The first centers on targeting healthcare organizations that offer consultations over the Internet and sending them booby-trapped medical records for the “patient.” The other involves carefully editing email inboxes of public company executives to make it appear that some were involved in insider trading.

Alex Holden is founder of Hold Security, a Milwaukee-based cybersecurity firm. Holden’s team gained visibility into discussions among members of two different ransom groups: CLOP (a.k.a. “Cl0p” a.k.a. “TA505“), and a newer ransom group known as Venus.

Last month, the U.S. Department of Health and Human Services (HHS) warned that Venus ransomware attacks were targeting a number of U.S. healthcare organizations. First spotted in mid-August 2022, Venus is known for hacking into victims’ publicly-exposed Remote Desktop services to encrypt Windows devices.

Holden said the internal discussions among the Venus group members indicate this gang has no problem gaining access to victim organizations.

“The Venus group has problems getting paid,” Holden said. “They are targeting a lot of U.S. companies, but nobody wants to pay them.”

Which might explain why their latest scheme centers on trying to frame executives at public companies for insider trading charges. Venus indicated it recently had success with a method that involves carefully editing one or more email inbox files at a victim firm — to insert messages discussing plans to trade large volumes of the company’s stock based on non-public information.

“We imitate correspondence of the [CEO] with a certain insider who shares financial reports of his companies through which your victim allegedly trades in the stock market, which naturally is a criminal offense and — according to US federal laws [includes the possibility of up to] 20 years in prison,” one Venus member wrote to an underling.

“You need to create this file and inject into the machine(s) like this so that metadata would say that they were created on his computer,” they continued. “One of my clients did it, I don’t know how. In addition to pst, you need to decompose several files into different places, so that metadata says the files are native from a certain date and time rather than created yesterday on an unknown machine.”

Holden said it’s not easy to plant emails into an inbox, but it can be done with Microsoft Outlook .pst files, which the attackers may also have access to if they’d already compromised a victim network.

“It’s not going to be forensically solid, but that’s not what they care about,” he said. “It still has the potential to be a huge scandal — at least for a while — when a victim is being threatened with the publication or release of these records.”

The Venus ransom group’s extortion note. Image: Tripwire.com

Holden said the CLOP ransomware gang has a different problem of late: Not enough victims. The intercepted CLOP communication seen by KrebsOnSecurity shows the group bragged about twice having success infiltrating new victims in the healthcare industry by sending them infected files disguised as ultrasound images or other medical documents for a patient seeking a remote consultation.

The CLOP members said one tried-and-true method of infecting healthcare providers involved gathering healthcare insurance and payment data to use in submitting requests for a remote consultation on a patient who has cirrhosis of the liver.

“Basically, they’re counting on doctors or nurses reviewing the patient’s chart and scans just before the appointment,” Holden said. “They initially discussed going in with cardiovascular issues, but decided cirrhosis or fibrosis of the liver would be more likely to be diagnosable remotely from existing test results and scans.”

While CLOP as a money making collective is a fairly young organization, security experts say CLOP members hail from a group of Threat Actors (TA) known as “TA505,” which MITRE’s ATT&CK database says is a financially motivated cybercrime group that has been active since at least 2014. “This group is known for frequently changing malware and driving global trends in criminal malware distribution,” MITRE assessed.

In April, 2021, KrebsOnSecurity detailed how CLOP helped pioneer another innovation aimed at pushing more victims into paying an extortion demand: Emailing the ransomware victim’s customers and partners directly and warning that their data would be leaked to the dark web unless they can convince the victim firm to pay up.

Security firm Tripwire points out that the HHS advisory on Venus says multiple threat actor groups are likely distributing the Venus ransomware. Tripwire’s tips for all organizations on avoiding ransomware attacks include:

While the above tips are important and useful, one critical area of ransomware preparedness overlooked by too many organizations is the need to develop — and then periodically rehearse — a plan for how everyone in the organization should respond in the event of a ransomware or data ransom incident. Drilling this breach response plan is key because it helps expose weaknesses in those plans that could be exploited by the intruders.

As noted in last year’s story Don’t Wanna Pay Ransom Gangs? Test Your Backups, experts say the biggest reason ransomware targets and/or their insurance providers still pay when they already have reliable backups of their systems and data is that nobody at the victim organization bothered to test in advance how long this data restoration process might take.

“Suddenly the victim notices they have a couple of petabytes of data to restore over the Internet, and they realize that even with their fast connections it’s going to take three months to download all these backup files,” said Fabian Wosar, chief technology officer at Emsisoft. “A lot of IT teams never actually make even a back-of-the-napkin calculation of how long it would take them to restore from a data rate perspective.”

Judge Orders U.S. Lawyer in Russian Botnet Case to Pay Google

lundi 5 décembre 2022 à 20:44

In December 2021, Google filed a civil lawsuit against two Russian men thought to be responsible for operating Glupteba, one of the Internet’s largest and oldest botnets. The defendants, who initially pursued a strategy of counter suing Google for tortious interference in their sprawling cybercrime business, later brazenly offered to dismantle the botnet in exchange for payment from Google. The judge in the case was not amused, found for the plaintiff, and ordered the defendants and their U.S. attorney to pay Google’s legal fees.

A slide from a talk given in Sept. 2022 by Google researcher Luca Nagy. https://www.youtube.com/watch?v=5Gz6_I-wl0E&t=6s

Glupteba is a rootkit that steals passwords and other access credentials, disables security software, and tries to compromise other devices on the victim network — such as Internet routers and media storage servers — for use in relaying spam or other malicious traffic.

Collectively, the tens of thousands of systems infected with Glupteba on any given day feed into a number of major cybercriminal businesses: The botnet’s proprietors sell the credential data they steal, use the botnet to place disruptive ads on the infected computers, and mine cryptocurrencies. Glupteba also rents out infected systems as “proxies,” directing third-party traffic through the infected devices to disguise the origin of the traffic.

In June 2022, KrebsOnSecurity showed how the malware proxy services RSOCKS and AWMProxy were entirely dependent on the Glupteba botnet for fresh proxies, and that the founder of AWMProxy was Dmitry Starovikov — one of the Russian men named in Google’s lawsuit.

Google sued Starovikov and 15 other “John Doe” defendants, alleging violations of the Racketeer Influenced and Corrupt Organizations Act (RICO), the Computer Fraud and Abuse Act, trademark and unfair competition law, and unjust enrichment.

In June, Google and the named defendants agreed that the case would proceed as a nonjury action because Google had withdrawn its claim for damages — seeking only injunctive relief to halt the operations of the botnet.

The defendants, who worked for a Russian firm called “Valtron” that was also named in the lawsuit, told Google that they were interested in settling. The defendants said they could potentially help Google by taking the botnet offline.

Another slide from Google researcher Luca Nagy’s September 2022 talk on Glupteba.

But the court expressed frustration that the defendants were unwilling to consent to a permanent injunction, and at the same time were unable to articulate why an injunction forbidding them from engaging in unlawful activities would pose a problem.

“The Defendants insisted that they were not engaged in criminal activity, and that any alleged activity in which they were engaged was legitimate,” U.S. District Court Judge Denise Cote wrote. “Nevertheless, the Defendants resisted entry of a permanent injunction, asserting that Google’s use of the preliminary injunction had disrupted their normal business operations.”

While the defendants represented that they had the ability to dismantle the Glupteba botnet, when it came time for discovery — the stage in a lawsuit where both parties can compel the production of documents and other information pertinent to their case — the attorney for the defendants told the court his clients had been fired by Valtron in late 2021, and thus no longer had access to their work laptops or the botnet.

The lawyer for the defendants — New York-based cybercrime defense attorney Igor Litvak — told the court he first learned about his clients’ termination from Valtron on May 20, a fact Judge Cote said she found “troubling” given statements he made to the court after that date representing that his clients still had access to the botnet.

The court ultimately suspended the discovery process against Google, saying there was reason to believe the defendants sought discovery only “to learn whether they could circumvent the steps Google has taken to block the malware.”

On September 6, Litvak emailed Google that his clients were willing to discuss settlement.

“The parties held a call on September 8, at which Litvak explained that the Defendants would be willing to provide Google with the private keys for Bitcoin addresses associated with the Glupteba botnet, and that they would promise not to engage in their alleged criminal activity in the future (without any admission of wrongdoing),” the judge wrote.

“In exchange, the Defendants would receive Google’s agreement not to report them to law enforcement, and a payment of $1 million per defendant, plus $110,000 in attorney’s fees,” Judge Cote continued. “The Defendants stated that, although they do not currently have access to the private keys, Valtron would be willing to provide them with the private keys if the case were settled. The Defendants also stated that they believe these keys would help Google shut down the Glupteba botnet.”

Google rejected the defendants’ offer as extortionate, and reported it to law enforcement. Judge Cote also found Litvak was complicit in the defendants’ efforts to mislead the court, and ordered him to join his clients in paying Google’s legal fees.

“It is now clear that the Defendants appeared in this Court not to proceed in good faith to defend against Google’s claims but with the intent to abuse the court system and discovery rules to reap a profit from Google,” Judge Cote wrote.

Litvak has filed a motion to reconsider (PDF), asking the court to vacate the sanctions against him. He said his goal is to get the case back into court.

“The judge was completely wrong to issue sanctions,” Litvak said in an interview with KrebsOnSecurity. “From the beginning of the case, she acted as if she needed to protect Google from something. If the court does not decide to vacate the sanctions, we will have to go to the Second Circuit (Court of Appeals) and get justice there.”

In a statement on the court’s decision, Google said it will have significant ramifications for online crime, and that since its technical and legal attacks on the botnet last year, Google has observed a 78 percent reduction in the number of hosts infected by Glupteba.

“While Glupteba operators have resumed activity on some non-Google platforms and IoT devices, shining a legal spotlight on the group makes it less appealing for other criminal operations to work with them,” reads a blog post from Google’s General Counsel Halimah DeLaine Prado and vice president of engineering Royal Hansen. “And the steps [Google] took last year to disrupt their operations have already had significant impact.”

A report from the Polish computer emergency response team (CERT Orange Polksa) found Glupteba was the biggest malware threat in 2021.

ConnectWise Quietly Patches Flaw That Helps Phishers

jeudi 1 décembre 2022 à 20:35

ConnectWise, a self-hosted, remote desktop software application that is widely used by Managed Service Providers (MSPs), is warning about an unusually sophisticated phishing attack that can let attackers take remote control over user systems when recipients click the included link. The warning comes just weeks after the company quietly patched a vulnerability that makes it easier for phishers to launch these attacks.

A phishing attack targeting MSP customers using ConnectWise.

ConnectWise’s service is extremely popular among MSPs that manage, protect and service large numbers of computers remotely for client organizations. Their product provides a dynamic software client and hosted server that connects two or more computers together, and provides temporary or persistent remote access to those client systems.

When a support technician wants to use ConnectWise to remotely administer a computer, the ConnectWise website generates an executable file that is digitally signed by ConnectWise and downloadable by the client via a hyperlink.

When the remote user in need of assistance clicks the link, their computer is then directly connected to the computer of the remote administrator, who can then control the client’s computer as if they were seated in front of it.

While modern Microsoft Windows operating systems by default will ask users whether they want to run a downloaded executable file, many systems set up for remote administration by MSPs disable that user account control feature for this particular application.

In October, security researcher Ken Pyle alerted ConnectWise that their client executable file gets generated based on client-controlled parameters. Meaning, an attacker could craft a ConnectWise client download link that would bounce or proxy the remote connection from the MSP’s servers to a server that the attacker controls.

This is dangerous because many organizations that rely on MSPs to manage their computers often set up their networks so that only remote assistance connections coming from their MSP’s networks are allowed.

Using a free ConnectWise trial account, Pyle showed the company how easy it was to create a client executable that is cryptographically signed by ConnectWise and can bypass those network restrictions by bouncing the connection through an attacker’s ConnectWise control server.

“You as the attacker have full control over the link’s parameters, and that link gets injected into an executable file that is downloaded by the client through an unauthenticated Web interface,” said Pyle, a partner and exploit developer at the security firm Cybir. “I can send this link to a victim, they will click this link, and their workstation will connect back to my instance via a link on your site.”

A composite of screenshots researcher Ken Pyle put together to illustrate the ScreenConnect vulnerability.

On Nov. 29, roughly the same time Pyle published a blog post about his findings, ConnectWise issued an advisory warning users to be on guard against a new round email phishing attempts that mimic legitimate email alerts the company sends when it detects unusual activity on a customer account.

“We are aware of a phishing campaign that mimics ConnectWise Control New Login Alert emails and has the potential to lead to unauthorized access to legitimate Control instances,” the company said.

ConnectWise said it released software updates last month that included new protections against the misdirection vulnerability that Pyle reported.  But the company said there is no reason to believe the phishers they warned about are exploiting any of the issues reported by Pyle.

“Our team quickly triaged the report and determined the risk to partners to be minimal,” ConnectWise spokesperson Tarran Street said. “Nevertheless, the mitigation was simple and presented no risk to partner experience, so we put it into the then-stable 22.8 build and the then-canary 22.9 build, which were released as part of our normal release processes. Due to the low severity of the issue, we didn’t (and don’t plan to) issue a security advisory or alert, since we reserve those notifications for serious security issues.”

Pyle said he doubts the issue he reported is unrelated to the phishing attacks ConnectWise is warning about.

“They don’t want to talk about my work (no advisory), and they recommend applying the patch they issued in response to my work,” Pyle wrote when asked to comment on ConnectWise’s response.

The ConnectWise advisory warned users that before clicking any link that appears to come from their service, users should validate the content includes “domains owned by trusted sources,” and “links to go to places you recognize.”

But Pyle said this advice is not terribly useful for customers, because in his attack scenario the phishers can send emails directly from ConnectWise, and the short link that gets presented to the user is a wildcard domain that ends in ConnectWise’s own domain name — screenconnect.com. What’s more, examining the exceedingly long link generated by ConnectWise’s systems offers few insights to the average user.

“It’s signed by ConnectWise and comes from them, and if you sign up for a free trial instance, you can email people invites directly from them,” Pyle said.

ConnectWise’s warnings come amid breach reports from another major provider of cloud-based remote support technologies: GoTo disclosed on Nov. 30 that it is investigating a security incident involving “unusual activity within our development environment and third-party cloud storage services. The third-party cloud storage service is currently shared by both GoTo and its affiliate, the password manager service LastPass.

In its own advisory on the incident, LastPass said they believe the intruders leveraged information stolen during a previous intrusion in August 2022 to gain access to “certain elements of our customers’ information.”  However, LastPass maintains that its “customer passwords remain safely encrypted due to LastPass’s Zero Knowledge architecture.”

In short, that architecture means if you lose or forget your all-important master LastPass password — the one needed to unlock access to all of your other passwords stored with them — LastPass can’t help you with that, because they don’t store it. But that same architecture theoretically means that hackers who might break into LastPass’s networks can’t access that information either.