Microsoft SharePoint Zero-Day Chaos: Brace Yourself for Cyber Mayhem!

Hot Take:

Looks like Microsoft’s SharePoint Server has taken a dive into the deep end of the vulnerability pool, and unfortunately, it forgot its floaties. With a CVSS score of 9.8, it’s as if SharePoint is auditioning for a horror movie, and hackers are more than happy to play the role of the monster under the bed. Microsoft, you might want to speed up that patch before SharePoint starts charging rent to these webshells.

Key Points:

• Microsoft warns of a zero-day vulnerability in SharePoint Server, CVE-2025-53770, with a high CVSS score of 9.8.
• No patch available yet, but mitigations and detection guidance have been provided.
• Google Threat Intelligence Group reports active exploitation involving webshell installation and data exfiltration.
• Eye Security observed dozens of compromised systems with attacks traced back to mid-July.
• Microsoft recommends immediate implementation of mitigations and promises future updates.

SharePoint’s Uninvited Guests

In a plot twist no one saw coming, SharePoint Server users woke up to find their digital doors left wide open for cyber miscreants. Microsoft’s urgent telegram (or perhaps a more modern equivalent: an email) warned of a zero-day vulnerability, CVE-2025-53770, which is as menacing as it sounds with a CVSS score of 9.8. If this vulnerability were a roller coaster, it would come with a health warning for its sheer drop of danger. The absence of a patch means that SharePoint is like an open buffet for hackers, and they are feasting like it’s Thanksgiving.

Patch? Who Needs a Patch?

Microsoft, apparently. But don’t worry, they are hard at work concocting a solution while providing mitigations and detection guidance to keep the wolves at bay. Until then, it’s a game of digital whack-a-mole as organizations scramble to plug the leaks with AMSI integration and Defender AV. Microsoft is essentially saying: “Here’s a life raft while we build you a boat.” But, if Hollywood has taught us anything, it’s to never get too comfortable on a life raft.

Hackers, Assemble!

Google’s Threat Intelligence Group is on the case, reporting that threat actors are exploiting the vulnerability faster than you can say “cybersecurity breach.” These hackers are installing webshells like they’re redecorating a house, and they’re not stopping until they’ve made themselves at home in your server. With cryptographic secrets being exfiltrated, affected organizations might want to start considering a new home security system—because the old one just isn’t cutting it.

The Eye of the Storm

Meanwhile, researchers at Eye Security are playing detective, having discovered dozens of systems already compromised. The attacks can be traced back to mid-July, which means the hackers have had plenty of time to make a mess of things. It’s like discovering your fridge has been left open for a month, and now everything is spoiled. Eye Security’s findings are a grim reminder that in the world of cybersecurity, vigilance is key—or risk getting your digital milk stolen.

Microsoft’s SOS

Microsoft’s advisory is basically an SOS to SharePoint users: implement mitigations immediately, assume the worst, and start investigating like you’re auditioning for CSI: Cyber. CTO Charles Carmakal of Mandiant Consulting advises organizations to act as if their systems are already compromised. It’s the cybersecurity equivalent of locking your doors only after the burglars have already left with the TV.

Stay Tuned for the Next Episode

The story isn’t over yet, as Microsoft promises updates and additional guidance as they race to put out the fire. In the meantime, affected organizations must remain on high alert, because in this episode of “As the Cyber World Turns,” it’s anyone’s guess who or what will strike next. And as always, we’ll be here with the popcorn, ready to deliver the latest updates with a side of humor.