Patch tracker / CVE reference / CVE-2025-21357
CVE-2025-21357
CVE-2025-21357 is a medium severity Microsoft vulnerability with a CVSS score of 6.7. Microsoft has shipped the fix: deploy the update below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
Medium severity Microsoft vulnerability, CVSS 6.7. Fixed by 1 Microsoft security update.
Risk summary
Senserva AI Opinion for CVE-2025-21357
A second Outlook remote code execution bug, identical in severity and EPSS to the other Outlook CVE, rounds out the Outlook-related fixes in this batch. Both are Medium severity with minimal exploitation likelihood, making them candidates for standard rather than expedited patching.
Do this: Bundle this with the other Outlook RCE CVE in the same routine Office update pass.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2025-21357
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Updated August 7, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Full tracking and change history for CVE-2025-21357
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
Exploitation and severity
Not in the CISA KEV catalog. EPSS exploit probability <1%. CVSS 6.7 (Medium).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2025-21357
Lower priority: patch in your normal cycle. In Intune or Defender, confirm whether the fixing update KB5002656 are installed across the affected products. Senserva does this automatically across your tenant and flags every missing patch.
Apply the Microsoft security update below to fix CVE-2025-21357. 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.
Affected products
Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.