Vulnerabilities
CVE-2026-70186: ASP.NET Core Denial‑of‑Service Fixes Released
Microsoft has addressed a denial‑of‑service vulnerability in ASP.NET Core (CVE‑2026‑70186). The fix is included in the latest security updates, and the update table now links to the download and KB article for Visual Studio. Defenders should verify that ASP.NET Core is patched and that Visual Studio is updated.
What Happened
Microsoft identified a denial‑of‑service flaw in ASP.NET Core (CVE‑2026‑70186). The vulnerability could allow an attacker to exhaust server resources by sending specially crafted requests.
Impact
Systems running affected versions of ASP.NET Core could be rendered unavailable. The fix is included in the latest security update releases; no additional mitigations are required beyond applying the patch.
What to Do
- Confirm the ASP.NET Core runtime version on all servers.
- Apply the latest security update for ASP.NET Core from the Microsoft Update Catalog or via Windows Update.
- Verify that Visual Studio is updated to the latest version; the update table now includes direct download and KB links.
- Monitor logs for repeated denial‑of‑service attempts and ensure rate‑limiting or application firewall rules are in place.
Additional Resources
Microsoft Security Advisory: CVE‑2026‑70186 – see the KB article for detailed patch instructions.
Related vulnerabilities
CVE-2026-70181: ASP.NET Core Denial of Service Vulnerability – Update Required
Microsoft has issued a security update for ASP.NET Core to address CVE-2026-70181, a denial‑of‑service flaw that can be triggered by malformed HTTP requests. The fix is included in the latest ASP.NET Core runtime and SDK releases; defenders should apply the update immediately and monitor traffic for suspicious request patterns.
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CVE-2026-96233: ASP.NET Core Denial‑of‑Service Vulnerability Fixed in Latest .NET Builds
A flaw in ASP.NET Core allows attackers to trigger a denial‑of‑service via crafted HTTP requests. Microsoft has released patches for .NET 6.0 through 11.0; the fix is already in the latest builds. Defenders should verify and apply the updates and monitor for abnormal resource usage.
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CVE-2026-70179: ASP.NET Core Elevation of Privilege – Informational Update
Microsoft has released an informational update for CVE-2026-70179, an elevation of privilege flaw in ASP.NET Core. The update adds download and KB article links for Visual Studio, but the fixed builds remain unchanged. Defenders should verify that their ASP.NET Core deployments are on patched versions and review the updated documentation.
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CVE-2026-70188: ASP.NET Core Security Feature Bypass – Update Table Clarification
Microsoft updated its security updates table to add KB article links for ASP.NET Core 11.0 and Visual Studio. The vulnerability was already fixed; no new patches are required. Defenders should verify that their ASP.NET Core 11.0 deployments are up‑to‑date and review the KB articles for guidance.
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