Patch Tuesday - July 2026

Microsoft is publishing 622 vulnerabilities on July 2026 Patch Tuesday , including a record-breaking 416 Windows vulnerabilities. Microsoft is aware of exploitation in the wild for two of the vulnerabilities published today, both of which are listed on CISA KEV, as well as public disclosure for one other. As usual, browser vulns are not included in the Patch Tuesday count above. Rapid7 noted last month that Microsoft no longer enumerates Chromium CVEs in the Security Update Guide. However, Microsoft has now taken the pursuit of minimalism much further, since today’s Security Update Guide no longer lists out even Microsoft vulnerabilities! Instead, we now receive a summary table of vulnerability counts by product family, as well as a new slimline “Notable CVEs” section. All of this only serves to illustrate the recent industry-wide trend of exploding vulnerability report counts, with an associated uptick in the publication of remediations as a trailing indicator. SharePoint: critical auth bypass by Rapid7 Today sees the publication of CVE-2026-55040 , a critical authentication bypass in Microsoft SharePoint. Discovered by Rapid7 Senior Principal Security Researcher Stephen Fewer , and published today in coordination with Microsoft, this vulnerability is the first in a pair of exploits which, when chained together, can lead to unauthenticated remote code execution against a vulnerable SharePoint server. Patches are available for SharePoint Server Subscription Edition, 2019, and 2016. As the full Rapid7 blog post sets out, the second vulnerability in the full RCE chain remains embargoed for now, with Microsoft expected to publish patches for that second vulnerability as part of Patch Tuesday August 2026. Microsoft noted: “We would like to thank Rapid7 for responsibly reporting this issue through coordinated vulnerability disclosure.” SharePoint: zero-day EoP It’s a rare Patch Tuesday which doesn’t include multiple SharePoint fixes, and today is no exception. Microsoft is aware of existing in-the-wild exploitation of CVE-2026-56164 , where successful exploitation allows an attacker to elevate privileges over a network, with no existing privileges required, and low attack complexity since “an attacker does not require significant prior knowledge of the system, and can achieve repeatable success”. This is as good an example as any that a relatively low CVSS v3 base score (5.3) may be an imperfect signal concealing something much spicier, and Microsoft acknowledges that possibility by assigning a severity rating of Important. Microsoft certainly intended to list CVE-2026-56164 in the new Notable CVEs section of the Security Update Guide instead of erroneously listing CVE-2026-56155 twice, and it’s likely that this will be corrected shortly. What’s the opposite of coordinated disclosure? After years of relative stability, the Patch Tuesday process has experienced significant turbulence so far in 2026. As well as the AI-fuelled exponential growth of vulne