Zoom’s troubled year just got worse.

Now that a large portion of the world is working from home to ride out the coronavirus pandemic, Zoom’s popularity has rocketed, but also has led to an increased focus on the company’s security practices and privacy promises. Hot on the heels of two security researchers finding a Zoom bug that can be abused to steal Windows passwords, another security researcher found two new bugs that can be used to take over a Zoom user’s Mac, including tapping into the webcam and microphone.

Patrick Wardle, a former NSA hacker and now principal security researcher at Jamf, dropped the two previously undisclosed flaws on his blog Wednesday, which he shared with TechCrunch.

The two bugs, Wardle said, can be launched by a local attacker — that’s where someone has physical control of a vulnerable computer. Once exploited, the attacker can gain and maintain persistent access to the innards of a victim’s computer, allowing them to install malware or spyware.

Wardle’s first bug piggybacks off a previous finding. Zoom uses a “shady” technique — one that’s also used by Mac malware — to install the Mac app without user interaction. Wardle found that a local attacker with low-level user privileges can inject the Zoom installer with malicious code to obtain the highest level of user privileges, known as “root.”

Those root-level user privileges mean the attacker can access the underlying macOS operating system, which are typically off-limits to most users, making it easier to run malware or spyware without the user noticing.

The second bug exploits a flaw in how Zoom handles the webcam and microphone on Macs. Zoom, like any app that needs the webcam and microphone, first requires consent from the user. But Wardle said an attacker can inject malicious code into Zoom to trick it into giving the attacker the same access to the webcam and microphone that Zoom already has. Once Wardle tricked Zoom into loading his malicious code, the code will “automatically inherit” any or all of Zoom’s access rights, he said — and that includes Zoom’s access to the webcam and microphone.

“No additional prompts will be displayed, and the injected code was able to arbitrarily record audio and video,” wrote Wardle.

Because Wardle dropped detail of the vulnerabilities on his blog, Zoom has not yet provided a fix. Zoom also did not respond to TechCrunch’s request for comment.

In the meanwhile, Wardle said, “if you care about your security and privacy, perhaps stop using Zoom.”

Source: Ex-NSA hacker drops new zero-day doom for Zoom | TechCrunch

Today, news of a Zoom issue affecting Microsoft Windows users. The Zoom Windows client is at risk from a flaw in the chat feature that could allow attackers to steal the logins of people who click on a link, according to tech site Bleeping Computer.

When using Zoom, it’s possible for people to communicate with each other via text message in a chat interface. When a chat message is sent containing a URL, this is converted into a hyperlink that others can click on to open a webpage in their browser.

But the Zoom client apparently also turns Windows networking Universal Naming Convention (UNC) paths into a clickable link in the chat messages, security researcher @_g0dmode has found.

MORE FROM FORBESBeware Zoom Users: Here’s How People Can ‘Zoom-Bomb’ Your ChatBy Kate O’Flaherty

Ok, so what’s the problem?

Bleeping Computer demonstrated how regular URL and the UNC path of \\evil.server.com\images\cat.jpg were both converted into a clickable link in the chat message.

The problem with this is, according to Bleeping Computer: “When a user clicks on a UNC path link, Windows will attempt to connect to a remote site using the SMB file sharing protocol to open the remote cat.jpg file.”

And at the same time, by default, Windows sends a user’s login name and NTLM password hash. This can be cracked fairly easily by an attacker to reveal your password.

Security researcher Matthew Hickey posted an example of exploiting the Zoom Windows client using UNC path injection on Twitter.

Source: Zoom User Warning: This Is How Attackers Could Steal Windows Passwords

Every day, a new Zoom security or privacy issue emerges. At least, that’s the way it seems during the COVID-19 crisis as an increasing number of people use the Zoom video conferencing app while working from home.

Soon after a security problem was disclosed that could allow attackers to steal Windows passwords, another researcher has identified two issues that can be used to take over a Zoom user’s Mac–and the microphone and webcam, according to TechCrunch.

The two bugs found by security researcher Patrick Wardle can be used by a local attacker able to gain physical control of a vulnerable Mac. By exploiting the bugs, the adversary can gain access to your computer and install malware or spyware, he wrote in a blog published today.

The first bug is based on another finding by @c1truz_, technical lead at a U.S. threat detection firm called VMRay. He said earlier this week on Twitter: “Ever wondered how the @zoom_us macOS installer does its job without you ever clicking install? Turns out they (ab)use preinstallation scripts, manually unpack the app using a bundled 7zip and install it to /Applications if the current user is in the admin group (no root needed).”

Source: Zoom Users Beware: Here’s How A Flaw Allows Attackers To Take Over Your Mac Microphone And Webcam