macOS Big Sur 11.4 Addresses Vulnerability That Could Let Attackers Take Secret Screenshots

macOS Big Sur 11.4, which was released this morning, addresses a zero-day vulnerability that could allow attackers to piggyback off of apps like Zoom, taking secret screenshots and surrepetiously recording the screen.

jamf malware secret screenshots
Jamf, a mobile device management company, today highlighted a security issue that allowed Privacy preferences to be bypassed, providing an attacker with Full Disk Access, Screen Recording, and other permissions without a user's consent.

The bypass was actively exploited in the wild, and was discovered by Jamf when analyzing XCSSET malware. The XCSSET malware has been out in the wild since 2020, but Jamf noticed an uptick in recent activity and discovered a new variant.

Once installed on a victim's system, the malware was used specifically for taking screenshots of the user's desktop with no additional permissions required. Jamf said that it could be used to bypass other permissions as well, as long as the donor application the malware piggybacked off of had that permission enabled.

Jamf has a full rundown on how the exploit worked, and the company says that Apple addressed the vulnerability in macOS Big Sur 11.4, Apple confirmed to TechCrunch that a fix has indeed been enabled in macOS 11.4, so Mac users should update their software as soon as possible.

Related Forum: macOS Big Sur

Popular Stories

Generic iOS 19 Feature Mock Light

iOS 19 Leak Reveals All-New Design

Friday January 17, 2025 2:42 pm PST by
iOS 19 is still around six months away from being announced, but a new leak has allegedly revealed a completely redesigned Camera app. Based on footage it obtained, YouTube channel Front Page Tech shared a video showing what the new Camera app will apparently look like, with the key change being translucent menus for camera controls. Overall, the design of these menus looks similar to...
2024 iPhone Boxes Feature

Apple Changes Trade-In Values for iPhones, iPads, Macs, and More

Thursday January 16, 2025 6:45 am PST by
Apple today adjusted estimated trade-in values for select iPhone, iPad, Mac, and Apple Watch models in the U.S., according to its website. Some values increased, while others decreased. The changes were not too significant, with most values rising or dropping by $5 to $50. We have outlined some examples below: Device New Value Old Value iPhone 15 Pro Max Up to $630 U ...
2024 App Store Awards

Apple Explains Why It Removed TikTok From the App Store in the U.S.

Sunday January 19, 2025 6:58 am PST by
Apple on late Saturday removed TikTok from the App Store in the U.S., and it has now explained why it was required to take this action. Last year, the U.S. passed a law that required Chinese company ByteDance to divest its ownership of TikTok due to potential national security risks, or else the platform would be banned. That law went into effect today, and companies like Apple and Google...
Generic iOS 18

Everything New in iOS 18.3 Beta 3

Thursday January 16, 2025 12:39 pm PST by
Apple provided the third beta of iOS 18.3 to developers today, and while the betas have so far been light on new features, the third beta makes some major changes to Notification Summaries and also tweaks a few other features. Notification Summary Changes Apple made multiple changes to Notification Summaries in response to complaints about inaccurate summaries of news headlines. For...
iOS 19 Roundup Feature

iOS 19 Rumored to Be Compatible With These iPhones

Saturday January 18, 2025 10:28 am PST by
iOS 19 will not drop support for any iPhone models, according to French website iPhoneSoft.fr. The report cited a source who said iOS 19 will be compatible with any iPhone that can run iOS 18, which would mean the following models: iPhone 16 iPhone 16 Plus iPhone 16 Pro iPhone 16 Pro Max iPhone 15 iPhone 15 Plus iPhone 15 Pro iPhone 15 Pro Max iPhone 14 iPhon...
iPad Pro vs iPhone 17 Air Feature

Here's How Thin the iPhone 17 Air Might Be

Friday January 17, 2025 3:38 pm PST by
For the last several months, we've been hearing rumors about a redesigned version of the iPhone 17 that Apple might call the iPhone 17 "Air," or something along those lines. It's going to replace the iPhone 17 Plus as Apple's fourth iPhone option, and it will be offered alongside the iPhone 17, iPhone 17 Pro, and iPhone 17 Pro Max. We know the iPhone 17 Air is going to be super slim, but...
apple power beats pro 2

Powerbeats Pro 2 Coming Soon: Apple to Announce Them 'Imminently'

Sunday January 19, 2025 8:25 am PST by
In September, Apple said that it would be launching Powerbeats Pro 2 in 2025, and it appears the wireless earbuds are coming very soon. Powerbeats Pro 2 images found in iOS 18 code In his Power On newsletter today, Bloomberg's Mark Gurman said the Powerbeats Pro 2 are "due imminently." In addition to Apple filing the Powerbeats Pro 2 in regulatory databases last month, Gurman said Apple is...
airtag 4 pack blue

AirTag 2 Launching This Year With These 3 New Features

Sunday January 19, 2025 8:11 am PST by
After a four-year wait, a new AirTag is finally expected to launch in 2025. Below, we recap rumored upgrades for the accessory. A few months ago, Bloomberg's Mark Gurman said Apple was aiming to release the AirTag 2 around the middle of 2025. While he did not offer a more specific timeframe, that means the AirTag 2 could be announced by the end of June. The original AirTag was announced...

Top Rated Comments

Kung gu Avatar
48 months ago
11.4 also fixes excessive ssd writes.

PSA: The SSD disk write issues have been fixed in 11.4 which came out today. The person who found the issue in first place says it was a result of a kernel bug and he also says 11.4 addresses the issue.
Update to 11.4 if your on M1 macs.
Users on this thread also report lower disk writes on 11.4.


[MEDIA=twitter]1396374313591140357[/MEDIA]
Score: 17 Votes (Like | Disagree)
Apple_Robert Avatar
48 months ago

OK just read the report by JAMF. So it piggybacks on fake Xcode projects, then requires the user to grant access through the Terminal and also through System Preferences. I'm glad this was found and dealt with, but it seems like it's a pretty weak exploit since nearly all of these behaviors should alert a user with more than 2 brain cells to stop the process
Unfortunately, a lot of people click accept without really thinking about what they are giving system access to and for what reason.
Score: 11 Votes (Like | Disagree)
deevey Avatar
48 months ago

Unfortunately, a lot of people click accept without really thinking about what they are giving system access to and for what reason.
And that folks, is why iOS should remain locked down tight :)
Score: 10 Votes (Like | Disagree)
Rigby Avatar
48 months ago

I assume this will be backported?
According to the post by JAMF it only affects MacOS 11. The security updates for Mojave ('https://support.apple.com/en-us/HT212531') and Catalina ('https://support.apple.com/en-us/HT212530') that also came out today do not list it.
Score: 8 Votes (Like | Disagree)
Guyferd Avatar
48 months ago

So how was it installed? The usual pirated software? Tricking users into downloading it as a fake utility or game?
OK just read the report by JAMF. So it piggybacks on fake Xcode projects, then requires the user to grant access through the Terminal and also through System Preferences. I'm glad this was found and dealt with, but it seems like it's a pretty weak exploit since nearly all of these behaviors should alert a user with more than 2 brain cells to stop the process
Score: 8 Votes (Like | Disagree)
TheYayAreaLiving ?️ Avatar
48 months ago
Thank you for the heads up. Hide your identity and yourself people!!!



Attachment Image
Score: 7 Votes (Like | Disagree)