Microsoft Corp. today issued security updates to fix more than 80 vulnerabilities in its Windows operating systems and software. There are no known “zero-day” or actively exploited vulnerabilities in this month’s bundle from Redmond, which nevertheless includes patches for 13 flaws that earned Microsoft’s most-dire “critical” label. Meanwhile, both Apple and Google recently released updates to fix zero-day bugs in their devices.

Microsoft assigns security flaws a “critical” rating when malware or miscreants can exploit them to gain remote access to a Windows system with little or no help from users. Among the more concerning critical bugs quashed this month is CVE-2025-54918. The problem here resides with Windows NTLM, or NT LAN Manager, a suite of code for managing authentication in a Windows network environment.

Redmond rates this flaw as “Exploitation More Likely,” and although it is listed as a privilege escalation vulnerability, Kev Breen at Immersive says this one is actually exploitable over the network or the Internet.

“From Microsoft’s limited description, it appears that if an attacker is able to send specially crafted packets over the network to the target device, they would have the ability to gain SYSTEM-level privileges on the target machine,” Breen said. “The patch notes for this vulnerability state that ‘Improper authentication in Windows NTLM allows an authorized attacker to elevate privileges over a network,’ suggesting an attacker may already need to have access to the NTLM hash or the user’s credentials.”

Breen said another patch — CVE-2025-55234, a 8.8 CVSS-scored flaw affecting the Windows SMB client for sharing files across a network — also is listed as privilege escalation bug but is likewise remotely exploitable. This vulnerability was publicly disclosed prior to this month.

“Microsoft says that an attacker with network access would be able to perform a replay attack against a target host, which could result in the attacker gaining additional privileges, which could lead to code execution,” Breen noted.

CVE-2025-54916 is an “important” vulnerability in Windows NTFS — the default filesystem for all modern versions of Windows — that can lead to remote code execution. Microsoft likewise thinks we are more than likely to see exploitation of this bug soon: The last time Microsoft patched an NTFS bug was in March 2025 and it was already being exploited in the wild as a zero-day.

“While the title of the CVE says ‘Remote Code Execution,’ this exploit is not remotely exploitable over the network, but instead needs an attacker to either have the ability to run code on the host or to convince a user to run a file that would trigger the exploit,” Breen said. “This is commonly seen in social engineering attacks, where they send the user a file to open as an attachment or a link to a file to download and run.”

Critical and remote code execution bugs tend to steal all the limelight, but Tenable Senior Staff Research Engineer Satnam Narang notes that nearly half of all vulnerabilities fixed by Microsoft this month are privilege escalation flaws that require an attacker to have gained access to a target system first before attempting to elevate privileges.

“For the third time this year, Microsoft patched more elevation of privilege vulnerabilities than remote code execution flaws,” Narang observed.

On Sept. 3, Google fixed two flaws that were detected as exploited in zero-day attacks, including CVE-2025-38352, an elevation of privilege in the Android kernel, and CVE-2025-48543, also an elevation of privilege problem in the Android Runtime component.

Also, Apple recently patched its seventh zero-day (CVE-2025-43300) of this year. It was part of an exploit chain used along with a vulnerability in the WhatsApp (CVE-2025-55177) instant messenger to hack Apple devices. Amnesty International reports that the two zero-days have been used in “an advanced spyware campaign” over the past 90 days. The issue is fixed in iOS 18.6.2, iPadOS 18.6.2, iPadOS 17.7.10, macOS Sequoia 15.6.1, macOS Sonoma 14.7.8, and macOS Ventura 13.7.8.

The SANS Internet Storm Center has a clickable breakdown of each individual fix from Microsoft, indexed by severity and CVSS score. Enterprise Windows admins involved in testing patches before rolling them out should keep an eye on askwoody.com, which often has the skinny on wonky updates.

AskWoody also reminds us that we’re now just two months out from Microsoft discontinuing free security updates for Windows 10 computers. For those interested in safely extending the lifespan and usefulness of these older machines, check out last month’s Patch Tuesday coverage for a few pointers.

As ever, please don’t neglect to back up your data (if not your entire system) at regular intervals, and feel free to sound off in the comments if you experience problems installing any of these fixes.

WhatsApp says it has issued an update to patch a vulnerability that has been used in conjunction with an Apple vulnerability to target specific users and compromise their devices.

Reportedly, attackers used this exploit against dozens of WhatsApp users, and WhatsApp has notified those affected:

“Our investigation indicates that a malicious message may have been sent to you through WhatsApp and combined with other vulnerabilities in your device’s operating system to compromise your device and the data it contains, including messages.

While we don’t know with certainty that your device has been compromised, we wanted to let you know out of an abundance of caution so you can take steps to secure your device and information.”

WhatsApp advised the affected users to perform a full factory reset of their phone in order to make sure they are rid of the malware.

“We’ve made changes to prevent this specific attack from occurring through WhatsApp. However, your device’s operating system could remain compromised by the malware or targeted in other ways.

To best protect yourself, we recommend a full device factory reset. We also strongly urge you to keep your devices updated to the latest version of the operating system, and ensure that your WhatsApp app is up to date.”

According to the Amnesty International Security Lab, the vulnerability was part of a zero-click attack against both iPhone and Android users. A zero-click attack is a type of attack which allows the cybercriminals to break into devices or apps without the victim needing to click, tap, or respond to anything. Unlike classic scams that rely on tricking someone into clicking a sketchy link, zero-click threats can land on a device simply because an app receives a message or notification crafted to exploit a hidden flaw.

Technical details

The zero-click attack required two vulnerabilities.

For iOS and Mac users these vulnerabilities were tracked as CVE-2025-43300 and lie in the Image I/O framework, the part of macOS and iOS that an app needs to open or save a picture. The problem came from an out-of-bounds write. Apple stepped in and tightened the rules with better bounds checking, closing off the hole so attackers can no longer use it.

An out-of-bounds write vulnerability means that the attacker can manipulate parts of the device’s memory that should be out of their reach. Such a flaw in a program allows it to read or write outside the bounds the program sets, enabling attackers to manipulate other parts of the memory allocated to more critical functions. Attackers can write code to a part of the memory where the system executes it with permissions that the program and user should not have.

In this case, an attacker could construct an image to exploit the vulnerability.  Processing such a malicious image file would result in memory corruption. Attackers can exploit memory corruption flaws to crash important processes or execute their own code.

The second vulnerability, CVE-2025-55177 for WhatsApp users, is caused by incomplete authorization of linked device synchronization messages in WhatsApp for iOS prior to v2.25.21.73, WhatsApp Business for iOS v2.25.21.78, and WhatsApp for Mac v2.25.21.78 and could have allowed an unrelated user to trigger processing of content from an arbitrary URL on a target’s device.

What to do

The infection chain described in the security advisories from Apple and WhatsApp relies on two components: an Apple vulnerability (CVE-2025-43300) in the Image I/O framework and a WhatsApp vulnerability (CVE-2025-55177) that allowed the hijacking of devices by synchronizing messages.

Attackers exploited the Apple ImageIO bug via malicious image files, which is dangerous because this core library is used by multiple apps (not just WhatsApp) for opening and previewing pictures. In affected WhatsApp versions for iOS and Mac, the sync message bug could trigger arbitrary URL processing, creating a powerful combo for chaining exploits and compromising devices without any user action.

While Android users were mentioned among potential targets in advanced spyware campaigns reported by Amnesty, the most severe zero-click risk described applies only to Apple devices. For Android, the WhatsApp vulnerability may have exposed users to attacks, but not via the same chained infection vectors. As always, updating WhatsApp and enabling advanced security features (like Google Advanced Protection on Android) is highly recommended. So is using security protection on your devices.

If you’ve received one of the notifications from WhatsApp, we’d advise you to follow the instructions.

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