Patch tracker / CVE reference / CVE-2025-26646
CVE-2025-26646
CVE-2025-26646 is a high severity Microsoft vulnerability with a CVSS score of 8.0. Microsoft has shipped the fix: deploy one of the 2 updates below from the Microsoft Update Catalog, and see where this CVE sits against the rest on the patch tracker.
High severity Microsoft vulnerability, CVSS 8.0. Fixed by 2 Microsoft security updates.
Risk summary
Updated July 24, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2025-26646
A spoofing vulnerability in .NET 8.0 and Visual Studio build tooling, High Severity at CVSS 8.0, and unusually it spans Windows, Linux, and macOS installs of the runtime. Spoofing in the build toolchain points at supply-chain style abuse: forged packages or build artifacts that developers and CI systems accept as authentic. EPSS is only 1 percent, so treat it as toolchain hygiene rather than incident response.
Do this: Update .NET 8.0 SDKs and runtimes across all three operating systems in your build farm and developer machines during the next tooling refresh.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2025-26646
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2025-26646
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 1.1%. CVSS 8.0 (High).
This CVE is among the lower half of tracked Microsoft CVEs by EPSS exploit probability.
Official patch(es) for CVE-2025-26646
Moderate priority: schedule it in your normal patch cycle. In Intune or Defender, confirm whether the fixing updates KB5059200, KB5059201 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-2025-26646. 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
Common questions about CVE-2025-26646
Is CVE-2025-26646 actively exploited?
It is not currently listed in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score puts the probability of exploitation in the next 30 days at 1.1%.
What patch fixes CVE-2025-26646?
Microsoft fixed CVE-2025-26646 in KB5059200, KB5059201. Download from the Microsoft Update Catalog, or let Intune, Windows Update, or WSUS deliver it.
Which products are affected by CVE-2025-26646?
.NET 8.0 installed on Linux, .NET 8.0 installed on Mac OS, .NET 8.0 installed on Windows.
Can I ask my own AI about CVE-2025-26646?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2025-26646's key facts: severity, CVSS, EPSS exploit probability, CISA KEV status, and the fixing KB. Copy it into Claude, ChatGPT, or Copilot for a triage plan; the data is refreshed three times a day (5 AM, 12:30 PM, and 7 PM US Central).
Authoritative references
Want every Microsoft CVE and the patches that fix it, ranked by real-world risk? See the Microsoft Patch Tracker.