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CVE-2017-0248

HIGH

CVE-2017-0248 is a high-severity (CVSS 7.5) CWE-295 vulnerability in microsoft .net framework. O3 Security detects and blocks CVE-2017-0248 exploitation at runtime via eBPF exploit-chain detection and L7 egress monitoring, even on unpatched systems.

Microsoft .NET Framework 2.0, 3.5, 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2 and 4.7 allow an attacker to bypass Enhanced Security Usage taggings when they present a certificate that is invalid…

Published
May 12, 2017
Updated
Jun 17, 2026
Affected
0 pkgs
Patched
None yet
Exploits
None indexed

Description

Microsoft .NET Framework 2.0, 3.5, 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2 and 4.7 allow an attacker to bypass Enhanced Security Usage taggings when they present a certificate that is invalid for a specific use, aka ".NET Security Feature Bypass Vulnerability."

Affected Products

1 product · 8 configurations
Application
.net frameworkmicrosoft
8 versions
2.03.53.5.14.5.24.64.6.14.6.24.7

Detection & mitigation playbook

Vendor / appliance
  1. Detect

    Inventory every microsoft .net framework deployment and check each version against the affected-products list above. Because the exploit targets the running system rather than your application code, also watch for exploitation at the network and runtime layer — O3 flags the exploit behaviour from runtime telemetry and egress traffic even before a vulnerable build is confirmed.

  2. Remediation status

    No patch has shipped for CVE-2017-0248 yet — track the microsoft .net framework advisory for a fixed release and apply the workarounds below in the meantime.

  3. Mitigate without a patch

    Cut exposure now: restrict the management/admin interface to trusted networks, segment the device, and apply the vendor's recommended configuration mitigations and any WAF/IPS signature. O3's runtime protection blocks the exploit chain at execution, holding the line on unpatched or end-of-life systems until you can patch.

  4. How O3 protects you

    O3 detects and blocks CVE-2017-0248 exploitation at runtime: eBPF exploit-chain detection, plus L7 egress monitoring that catches the post-exploitation callback and severs the attacker's outbound channel.

Tailored to CVE-2017-0248. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Microsoft .NET Framework 2.0, 3.5, 3.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2 and 4.7 allow an attacker to bypass Enhanced Security Usage taggings when they present a certificate that is invalid for a specific use, aka ".NET Security Feature Bypass Vulnerability."
O3 Security · Runtime Protection

Is CVE-2017-0248 being exploited in your environment?

O3's eBPF runtime sensors and L7 egress monitoring detect and block the CVE-2017-0248 exploit chain at execution — protecting unpatched and end-of-life systems until the vendor patch is applied.