Microsoft is addressing 67 vulnerabilities this June 2025 Patch Tuesday. Microsoft has evidence of in-the-wild exploitation for just one of the vulnerabilities published today, and that is reflected in CISA KEV. Separately, Microsoft is aware of existing public disclosure for one other freshly published vulnerability. Microsoft’s luck holds for a ninth consecutive Patch Tuesday, since neither of today’s zero-day vulnerabilities are evaluated as critical severity at time of publication. Today also sees the publication of eight critical remote code execution (RCE) vulnerabilities. Two browser vulnerabilities have already been published separately this month, and are not included in the total.

Windows WebDAV: zero-day RCE

Remember the WebDAV standard? It has been seven years since Microsoft has published a vulnerability in the Windows implementation of WebDAV, and today’s publication of CVE-2025-33053 is the first zero-day vulnerability on record. Originally dreamed up in the 1990s to support interactivity on the web, WebDAV may be familiar to Exchange admins and users of a certain vintage, since older versions of Exchange, up to and including Exchange Server 2010, supported WebDAV as a means for interacting with mailboxes and public folders.

It will surprise no one that Windows still more or less supports WebDAV, and that turns out to be a bit of a problem. Microsoft acknowledges Check Point Research (CPR) on the advisory; CPR in turn attributes exploitation of CVE-2025-33053 to an APT, which they track as Stealth Falcon, an established threat actor with a long-running interest in governments and government-adjacent entities across the Middle East and the surrounding area.

Curiously, the Microsoft advisory does not mention that the Windows implementation of WebDAV is listed as deprecated since November 2023, which in practical terms means that the WebClient service no longer starts by default. The advisory also has attack complexity as low, which means that exploitation does not require preparation of the target environment in any way that is beyond the attacker’s control. Exploitation relies on the user clicking a malicious link. It’s not clear how an asset would be immediately vulnerable if the service isn’t running, but all versions of Windows receive a patch, including those released since the deprecation of WebClient, like Server 2025 and Windows 11 24H2. On Server 2025, for instance, it’s still possible to install the WebDAV Redirector server feature, which then causes the WebClient service to appear.

SMB client: zero-day EoP

Publicly disclosed elevation of privilege (EoP) zero-day vulnerabilities that lead to SYSTEM are always going to be worth a closer look, and CVE-2025-33073 is no exception. The advisory sets out that the easiest path to exploitation simply requires the user to connect to a malicious SMB server controlled by the attacker. It’s not entirely clear from the advisory whether simply connecting is enough to trigger exploitation, or whether successful authentication is required, since there is currently conflicting language in two separate FAQ entries with almost-identical titles: “How could an attacker exploit this/the vulnerability?” It may well be that Microsoft will come back around and clarify this wording, but in the meantime the only safe assumption is that fortune favours the attacker.

Windows KDC Proxy: critical RCE

The Windows KDC Proxy Service (KPSSVC) receives a patch today for CVE-2025-33071, which describes a critical unauthenticated RCE vulnerability where exploitation is via abuse of a cryptographic protocol weakness. The good news is that only Windows Server assets configured as a Kerberos Key Distribution Center Proxy Protocol server — happily, this is not enabled as standard configuration for a domain controller — and exploitation requires that the attacker win a race condition. The bad news is that Microsoft considers exploitation more likely regardless, and since a KDC proxy helps Kerberos requests from untrusted networks more easily access trusted assets without any need for a direct TCP connection from the client to the domain controller, the trade-off here is that the KDC proxy itself is quite likely to be exposed to an untrusted network. Patching this vulnerability should be top of mind for affected defenders this month.

Office preview pane: trio of critical RCEs

Microsoft expects that exploitation of three Office critical RCE vulns patched today is more likely. CVE-2025-47162, CVE-2025-47164, and CVE-2025-47167 share several attributes: each was discovered by prolific researcher 0x140ce, who topped the MSRC 2025 Q1 leaderboard, and each includes the Preview Pane as a vector, which always ups the ante for defenders. Admins responsible for installations of Microsoft 365 Apps for Enterprise — also confusingly referred to as “Microsoft 365 for Office” in the advisory FAQ — will have to hang on, since patches for today’s vulnerabilities aren’t yet available for that particular facet of the Microsoft 365 kaleidoscope.

Microsoft lifecycle update

June is a quiet month for Microsoft product lifecycle changes. The next batch of significant Microsoft product lifecycle status changes are due in July 2025, when the SQL Server 2012 ESU program draws to a close, along with support for Visual Studio 2022 17.8 LTSC.

Summary tables

Azure vulnerabilities

Browser vulnerabilities

Developer Tools vulnerabilities

Microsoft Dynamics vulnerabilities

Microsoft Office vulnerabilities

Windows vulnerabilities

Windows ESU vulnerabilities

Microsoft is addressing 77 vulnerabilities this May 2025 Patch Tuesday. Microsoft has evidence of in-the-wild exploitation for five of the vulnerabilities published today, and these are already reflected in CISA KEV. Separately, Microsoft is aware of existing public disclosure for two vulnerabilities published today. This is now the eighth consecutive Patch Tuesday on which Microsoft has published zero-day vulnerabilities without evaluating any of them as critical severity at time of publication. Today also sees the publication of six critical remote code execution (RCE) vulnerabilities. Six browser vulnerabilities have already been published separately this month, and are not included in the total.

Windows Scripting Engine: zero-day RCE

In the majority of cases, the CVSSv3 base score provides a solid sense of the severity of a vulnerability. Sometimes, however, even a correct CVSS assessment can disguise the potential impact of a specific vulnerability. This is arguably the case with CVE-2025-30397, a zero-day RCE vulnerability in the Windows Scripting Engine with a healthy but unremarkable CVSSv3 base score of 7.5. Microsoft is aware of exploitation in the wild. It’s certainly not the worst of the worst — we save that level of alarm for pre-authentication RCE with no requirement for user interaction —  and Microsoft very reasonably assesses attack complexity as high. And yet…

The advisory FAQ for CVE-2025-30397 explains that successful exploitation requires an attacker to first prepare the target so that it uses Edge in Internet Explorer Mode, and then causes the user to click a malicious link; there is no mention of a requirement for the user to actively reload the page in Internet Explorer Mode, so we must assume that exploitation requires only that the “Allow sites to be reloaded in Internet Explorer” option is enabled. Users who are most likely to require Internet Explorer compatibility mode in 2025 are surely users at enterprise organizations, where critical business workflows still depend on applications from the dinosaur days when Internet Explorer ruled the roost. No doubt the concept of a plan for migration of all of these applications exists, buried several layers deep in a dusty backlog, but Microsoft would hardly be offering IE compatibility mode until at least 2029 if it didn’t know that a huge swathe of its customer base demands it.

If the pre-requisite conditions are already conveniently in place on the target asset thanks to a well-meaning corporate IT policy, attack complexity is suddenly nice and low. If this vulnerability didn’t have that requirement for environment preparation, the CVSS base score would then be 8.8, which is as close to critical as you can get without actually stepping over the line. As Rapid7 has previously noted on a number of occasions, the MSHTML/Trident scripting engine is still present in Windows; this is true even for assets which have only ever run versions of Windows released well after the end of support for Internet Explorer 11 back in June 2022.

Common Log File System: zero-day EoPs

CVE-2025-32701 and CVE-2025-32706 are far from the first zero-day vulnerabilities in the Windows Common Log File System (CLFS) driver; indeed, they are the latest members of an ongoing dynasty where exploitation typically leads to elevation of privilege to SYSTEM. Credit where credit is due: recent disclosures by Microsoft’s own Threat Intelligence Center (MSTIC), including this month’s CVE-2025-32701, demonstrate that Microsoft is putting serious effort into detecting and rooting out CLFS exploitation. Of course, since Microsoft is aware of exploitation in the wild, we know that someone else got there first, and there’s no reason to suspect that threat actors will stop looking for ways to abuse CLFS any time soon.

Windows Desktop Window Manager: zero-day EoP

If proof were needed that elevation of privilege to SYSTEM will never go out of style, today sees the publication of CVE-2025-30400, which is a zero-day vulnerability in the Windows Desktop Window Manager (DWM). As it happens, tomorrow marks the one-year anniversary of CVE-2024-30051, a previous zero-day EoP vulnerability in DWM.

Visual Studio: zero-day RCE

Today, all current versions of Visual Studio 2022 and 2019 receive patches for CVE-2025-32702, a zero-day RCE where exploitation requires the user to download and open a malicious file. There is nothing obviously remarkable about this, although Microsoft is aware of public disclosure. As usual for a malicious file/link vuln, the word Remote here refers to the location of the attacker, even though exploitation is set in motion by local user action.

Ancillary Function Driver for Winsock: zero-day EoP

Regular Patch Tuesday watchers will recognize the Ancillary Function Driver for Winsock, which is the site of CVE-2025-32709, an elevation of privilege vulnerability for which Microsoft is aware of exploitation. In something of a break with tradition for Patch Tuesday zero-day EoP vulnerabilities, exploitation only leads to administrator privileges rather than all the way to SYSTEM, but no attacker is going to waste too many cycles feeling sad about that.

Defender for Identity: situationally-ironic zero-day spoofing

Today sees the publication of CVE-2025-26685, a zero-day spoofing vulnerability in Microsoft Defender for Identity. The advisory provides puzzle pieces which don’t by themselves add up to anything like a full explanation of the vulnerability; no action is required for remediation, but you can render yourself vulnerable if you insist by opening a case with Microsoft Support to re-enable the legacy NTLM authentication method.

However, the FAQ does offer a link to an article published yesterday: Configure SAM-R to enable lateral movement path detection in Microsoft Defender for Identity. This solid piece of documentation is part of the overall Defender for Identity administration guide, and explains that the lateral movement path detection feature can itself potentially be exploited by an adversary to obtain an NTLM hash.

Exploitation relies on achieving fallback from Kerberos to NTLM; the compromised credentials in this case would be those of the Directory Service Account for Defender for Identity. The new Defender for Identity sensor (version 3.x) is not affected by this issue as it uses different detection methods; at time of writing, the Defender for Identity What’s new? page doesn’t yet describe the 3.x release, but this will presumably receive an update soon.

Microsoft lifecycle update

The next batch of significant Microsoft product lifecycle status changes are due in July 2025, when SQL Server 2012 ESU program draws to a close, along with support for Visual Studio 2022 17.8 LTSC.

Summary charts

Summary tables

Apps vulnerabilities

Azure vulnerabilities

Azure Windows vulnerabilities

Browser vulnerabilities

Developer Tools vulnerabilities

ESU Windows vulnerabilities

Microsoft Dynamics vulnerabilities

Microsoft Office vulnerabilities

Microsoft Office ESU Windows vulnerabilities

System Center vulnerabilities

Windows vulnerabilities

Microsoft is addressing 121 vulnerabilities this April 2025 Patch Tuesday, which is more than twice as many as last month. Microsoft has evidence of in-the-wild exploitation for just one of the vulnerabilities published today, which is already reflected in CISA KEV. Once again, Microsoft has published zero-day vulnerabilities on Patch Tuesday without evaluating any of them as critical severity at time of publication, so that’s now a seven month unbroken streak. Today also sees the publication of 11 critical remote code execution (RCE) vulnerabilities. 13 browser vulnerabilities have already been published separately this month, and are not included in the total.

CLFS: zero-day EoP

The Windows Common Log File System (CLFS) Driver is firmly back on our radar today with CVE-2025-29824, a zero-day local elevation of privilege vulnerability. First, the good news: the Acknowledgements section credits the Microsoft Threat Intelligence Center, so the exploit was successfully reproduced by Microsoft; the less-good news is that someone other than Microsoft was first to discover the exploit, because otherwise Microsoft wouldn’t be listing CVE-2025-29824 as exploited in the wild. The advisory does not specify what privilege level is achieved upon successful exploitation, but it’ll be SYSTEM, because that’s the prize for all the other CLFS elevation of privilege zero-day vulnerabilities. As usual, some form of less-privileged local access is a pre-requisite, but attack complexity is low, so this is the sort of vulnerability which goes into any standard break-and-enter toolkit. Given the long history of similar vulnerabilities, it would be more surprising if exploit code wasn’t publicly available in the not-too-distant future. Although December 2024 Patch Tuesday seems as though it must have been a very long time ago, any standard calendar will tell us that only 119 days have elapsed since the last zero-day CLFS local elevation of privilege. Rapid7 discussed the history of CLFS zero-day elevation of privilege vulnerabilities at the time. All versions of Windows receive a patch, except for the venerable LTSC Windows 10 1507, which is listed on the advisory as vulnerable, but left out in the cold with no update; the FAQ says to check back later. Windows 10 LTSC 1507 is scheduled for end of servicing on 2025-10-14, so the clock is ticking regardless.

LDAP Server: critical RCE

Although it has been many months since we’ve seen a critical zero-day vulnerability from Microsoft, there is no shortage of critical remote code execution (RCE) vulnerabilities published today. Defenders responsible for an LDAP server — which means almost any organization with a non-trivial Microsoft footprint — should add patching for CVE-2025-26663 to their to-do list. With no privileges required, no need for user interaction, and code execution presumably in the context of the LDAP server itself, successful exploitation would be an attractive shortcut to any attacker. Anyone wondering if today is a re-run of December 2024 Patch Tuesday can take some small solace in the fact that the worst of the trio of LDAP critical RCEs published at the end of last year was likely easier to exploit than today’s example, since today’s CVE-2025-26663 requires that an attacker win a race condition. Despite that, Microsoft still expects that exploitation is more likely.

LDAP Client: critical RCE

If you breathe a sigh of relief when you see LDAP server critical RCE vulnerabilities like CVE-2025-26663, because you’re certain that you don’t have any Windows LDAP servers in your estate, how about LDAP clients? CVE-2025-26670 describes a critical RCE in the LDAP client, although the FAQ confusingly states that exploitation would require an attacker to “send specially crafted requests to a vulnerable LDAP server”; this seems like it might be a data entry error on the advisory FAQ, so keep an eye out for an update to that section of the advisory. Assuming the rest of the advisory is all present and correct, exploitation requires that the attacker win a race condition, which keeps the attack complexity higher than it otherwise would be. While we wait for clarification, it’s still a critical RCE which Microsoft rates as “exploitation more likely”. On that basis, patching is always recommended.

RDS: critical RCEs

The prolific Windows vulnerability pioneers at Kunlun Lab are credited with a pair of critical RCE vulnerabilities in Windows Remote Desktop Services. Although both CVE-2025-27480 and CVE-2025-27482 share a CVSSv3 base score of 8.1, Microsoft has ranked them both as critical using its own proprietary severity ranking scale. Both vulnerabilities require that an attacker win a race condition. If you’ve ever read Microsoft’s guide to deploying the Remote Desktop Gateway role, you probably have some systems to patch.

Hyper-V: critical RCE

Some Microsoft security advisory FAQs provide a satisfying level of detail, whereas others raise more questions than they answer. CVE-2025-27491 is a Hyper-V critical RCE which falls into the second category, since it states that an attacker must be authenticated — no need for elevated privileges — but also that the attacker must send the user a malicious site and convince them to open it, and it’s not at all clear why authentication would be required in that case. Also unusual: the remediation table on the advisory lists several 32-bit versions of Windows as receiving patches, although Hyper-V requires a 64-bit processor and a 64-bit host OS.

Microsoft lifecycle update

In Microsoft product lifecycle news, Dynamics GP 2015 moves past the end of extended support today. The next batch of significant lifecycle status changes are due in July 2025, when SQL Server 2012 ESU program draws to a close.

Summary charts

Summary tables

Apps vulnerabilities

Azure vulnerabilities

Browser vulnerabilities

Developer Tools vulnerabilities

Developer Tools SQL Server vulnerabilities

Microsoft Dynamics vulnerabilities

Microsoft Office vulnerabilities

System Center vulnerabilities

Windows vulnerabilities

Windows Azure vulnerabilities

Windows ESU vulnerabilities

Windows ESU Microsoft Office vulnerabilities