Patch tracker / CVE reference / CVE-2025-27729

CVE-2025-27729

CVE-2025-27729 is a high severity Microsoft vulnerability with a CVSS score of 7.8. Its EPSS score puts the probability of exploitation in the next 30 days at 14%. Microsoft has shipped the fix: deploy one of the 3 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.

Risk summary

High
7.8
CVSS
14%
EPSS, 30 days
High
Severity

Not in the CISA KEV catalog. EPSS exploit probability 14%. CVSS 7.8 (High).

This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.

Senserva AI Opinion for CVE-2025-27729

Remote code execution through the Windows Shell itself, affecting Windows 10 21H2 across 32-bit, x64, and ARM64, at High Severity, CVSS 8.8. Shell bugs typically fire when a user browses to or previews malicious content, so exposure is broad on client machines. EPSS is 18 percent.

Do this: Push the Windows 10 21H2 cumulative update to end-user devices ahead of servers this cycle.

AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.

Senserva AI Opinion and rich prompt for CVE-2025-27729

Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.

Patch this cycle
Not confirmed exploited yet, but the 30-day exploit probability is high (EPSS 14%).
Fixed by KB5055518 and 2 more (by build, listed below). Download from the Microsoft Update Catalog, or deploy via Windows Update, Intune, or WSUS.
Do this now: Patch in this maintenance window; do not let it slip to the next one.

Official patch(es) for CVE-2025-27729

Elevated priority: high severity or a meaningful exploitation probability, sooner if an affected product is internet-facing. In Intune or Defender, confirm whether the fixing updates KB5055518, KB5055523, KB5055528 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.

Apply the Microsoft security updates below to fix CVE-2025-27729. Each KB page carries the Microsoft Update Catalog download, Microsoft's known issues for the update, a copy-paste PowerShell check for whether it is installed, and the Senserva AI read.

Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.

New to a term on this page? CVE, KB, KEV, CVSS, and EPSS are each explained once, on the Senserva security lexicon. Reference: Microsoft CVE and vulnerability management and the Microsoft patching guide.
Provided as is, without warranty; verify against the vendor advisory before acting. Data notice and terms.