Microsoft today released updates to fix more than 100 security flaws in its Windows operating systems and other software. At least 13 of the bugs received Microsoft’s most-dire “critical” rating, meaning they could be abused by malware or malcontents to gain remote access to a Windows system with little or no help from users.

August’s patch batch from Redmond includes an update for CVE-2025-53786, a vulnerability that allows an attacker to pivot from a compromised Microsoft Exchange Server directly into an organization’s cloud environment, potentially gaining control over Exchange Online and other connected Microsoft Office 365 services. Microsoft first warned about this bug on Aug. 6, saying it affects Exchange Server 2016 and Exchange Server 2019, as well as its flagship Exchange Server Subscription Edition.

Ben McCarthy, lead cyber security engineer at Immersive, said a rough search reveals approximately 29,000 Exchange servers publicly facing on the internet that are vulnerable to this issue, with many of them likely to have even older vulnerabilities.

McCarthy said the fix for CVE-2025-53786 requires more than just installing a patch, such as following Microsoft’s manual instructions for creating a dedicated service to oversee and lock down the hybrid connection.

“In effect, this vulnerability turns a significant on-premise Exchange breach into a full-blown, difficult-to-detect cloud compromise with effectively living off the land techniques which are always harder to detect for defensive teams,” McCarthy said.

CVE-2025-53779 is a weakness in the Windows Kerberos authentication system that allows an unauthenticated attacker to gain domain administrator privileges. Microsoft credits the discovery of the flaw to Akamai researcher Yuval Gordon, who dubbed it “BadSuccessor” in a May 2025 blog post. The attack exploits a weakness in “delegated Managed Service Account” or dMSA — a feature that was introduced in Windows Server 2025.

Some of the critical flaws addressed this month with the highest severity (between 9.0 and 9.9 CVSS scores) include a remote code execution bug in the Windows GDI+ component that handles graphics rendering (CVE-2025-53766) and CVE-2025-50165, another graphics rendering weakness. Another critical patch involves CVE-2025-53733, a vulnerability in Microsoft Word that can be exploited without user interaction and triggered through the Preview Pane.

One final critical bug tackled this month deserves attention: CVE-2025-53778, a bug in Windows NTLM, a core function of how Windows systems handle network authentication. According to Microsoft, the flaw could allow an attacker with low-level network access and basic user privileges to exploit NTLM and elevate to SYSTEM-level access — the highest level of privilege in Windows. Microsoft rates the exploitation of this bug as “more likely,” although there is no evidence the vulnerability is being exploited at the moment.

Feel free to holler in the comments if you experience problems installing any of these updates. As ever, the SANS Internet Storm Center has its useful breakdown of the Microsoft patches indexed by severity and CVSS score, and AskWoody.com is keeping an eye out for Windows patches that may cause problems for enterprises and end users.

GOOD MIGRATIONS

Windows 10 users out there likely have noticed by now that Microsoft really wants you to upgrade to Windows 11. The reason is that after the Patch Tuesday on October 14, 2025, Microsoft will stop shipping free security updates for Windows 10 computers. The trouble is, many PCs running Windows 10 do not meet the hardware specifications required to install Windows 11 (or they do, but just barely).

If the experience with Windows XP is any indicator, many of these older computers will wind up in landfills or else will be left running in an unpatched state. But if your Windows 10 PC doesn’t have the hardware chops to run Windows 11 and you’d still like to get some use out of it safely, consider installing a newbie-friendly version of Linux, like Linux Mint.

Like most modern Linux versions, Mint will run on anything with a 64-bit CPU that has at least 2GB of memory, although 4GB is recommended. In other words, it will run on almost any computer produced in the last decade.

There are many versions of Linux available, but Linux Mint is likely to be the most intuitive interface for regular Windows users, and it is largely configurable without any fuss at the text-only command-line prompt. Mint and other flavors of Linux come with LibreOffice, which is an open source suite of tools that includes applications similar to Microsoft Office, and it can open, edit and save documents as Microsoft Office files.

If you’d prefer to give Linux a test drive before installing it on a Windows PC, you can always just download it to a removable USB drive. From there, reboot the computer (with the removable drive plugged in) and select the option at startup to run the operating system from the external USB drive. If you don’t see an option for that after restarting, try restarting again and hitting the F8 button, which should open a list of bootable drives. Here’s a fairly thorough tutorial that walks through exactly how to do all this.

And if this is your first time trying out Linux, relax and have fun: The nice thing about a “live” version of Linux (as it’s called when the operating system is run from a removable drive such as a CD or a USB stick) is that none of your changes persist after a reboot. Even if you somehow manage to break something, a restart will return the system back to its original state.

Microsoft today released updates to fix at least 137 security vulnerabilities in its Windows operating systems and supported software. None of the weaknesses addressed this month are known to be actively exploited, but 14 of the flaws earned Microsoft’s most-dire “critical” rating, meaning they could be exploited to seize control over vulnerable Windows PCs with little or no help from users.

While not listed as critical, CVE-2025-49719 is a publicly disclosed information disclosure vulnerability, with all versions as far back as SQL Server 2016 receiving patches. Microsoft rates CVE-2025-49719 as less likely to be exploited, but the availability of proof-of-concept code for this flaw means its patch should probably be a priority for affected enterprises.

Mike Walters, co-founder of Action1, said CVE-2025-49719 can be exploited without authentication, and that many third-party applications depend on SQL server and the affected drivers — potentially introducing a supply-chain risk that extends beyond direct SQL Server users.

“The potential exposure of sensitive information makes this a high-priority concern for organizations handling valuable or regulated data,” Walters said. “The comprehensive nature of the affected versions, spanning multiple SQL Server releases from 2016 through 2022, indicates a fundamental issue in how SQL Server handles memory management and input validation.”

Adam Barnett at Rapid7 notes that today is the end of the road for SQL Server 2012, meaning there will be no future security patches even for critical vulnerabilities, even if you’re willing to pay Microsoft for the privilege.

Barnett also called attention to CVE-2025-47981, a vulnerability with a CVSS score of 9.8 (10 being the worst), a remote code execution bug in the way Windows servers and clients negotiate to discover mutually supported authentication mechanisms. This pre-authentication vulnerability affects any Windows client machine running Windows 10 1607 or above, and all current versions of Windows Server. Microsoft considers it more likely that attackers will exploit this flaw.

Microsoft also patched at least four critical, remote code execution flaws in Office (CVE-2025-49695, CVE-2025-49696, CVE-2025-49697, CVE-2025-49702). The first two are both rated by Microsoft as having a higher likelihood of exploitation, do not require user interaction, and can be triggered through the Preview Pane.

Two more high severity bugs include CVE-2025-49740 (CVSS 8.8) and CVE-2025-47178 (CVSS 8.0); the former is a weakness that could allow malicious files to bypass screening by Microsoft Defender SmartScreen, a built-in feature of Windows that tries to block untrusted downloads and malicious sites.

CVE-2025-47178 involves a remote code execution flaw in Microsoft Configuration Manager, an enterprise tool for managing, deploying, and securing computers, servers, and devices across a network. Ben Hopkins at Immersive said this bug requires very low privileges to exploit, and that it is possible for a user or attacker with a read-only access role to exploit it.

“Exploiting this vulnerability allows an attacker to execute arbitrary SQL queries as the privileged SMS service account in Microsoft Configuration Manager,” Hopkins said. “This access can be used to manipulate deployments, push malicious software or scripts to all managed devices, alter configurations, steal sensitive data, and potentially escalate to full operating system code execution across the enterprise, giving the attacker broad control over the entire IT environment.”

Separately, Adobe has released security updates for a broad range of software, including After Effects, Adobe Audition, Illustrator, FrameMaker, and ColdFusion.

The SANS Internet Storm Center has a breakdown of each individual patch, indexed by severity. If you’re responsible for administering a number of Windows systems, it may be worth keeping an eye on AskWoody for the lowdown on any potentially wonky updates (considering the large number of vulnerabilities and Windows components addressed this month).

If you’re a Windows home user, please consider backing up your data and/or drive before installing any patches, and drop a note in the comments if you encounter any problems with these updates.

ISSUE 22.25.1 • 2025-06-24 By Susan Bradley The June updates are a mixed bag. So far, I have not seen any side effects from this month’s updates. However, I am tracking some other issues that may impact businesses. That’s a problem, because I’m not sure what the root causes or triggers are. I just know […]