Untrusted search path in Microsoft .NET Framework enables local bypass
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-426.
Summary
Microsoft .NET Framework 3.5, 4.6.2/4.7/4.7.1/4.7.2, 4.8 and 4.8.1 are affected before their fixed builds. The framework uses an untrusted search path (CWE-426), which allows bypass of a security feature. A local attacker with low privileges can bypass the feature, with no user interaction needed.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
Description from the CNA
Untrusted search path in .NET Framework allows an authorized attacker to bypass a security feature locally.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Microsoft | Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 | 3.0.0.0 to before 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 | 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.7.2 | 4.7.0 to before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.8 | 4.8.0 to before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 | 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 3.5 AND 4.8.1 | 4.8.1 to before 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 | 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 | 4.7.0 to before 4.7.4150.0 | 4.7.4150.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 4.8 | 4.8.0 to before 4.8.4811.0 | 4.8.4811.0 | Patch available | CNA |
| Microsoft | Microsoft .NET Framework 4.8.1 | 4.8.0.0 to before 4.8.9363.0 | 4.8.9363.0 | Patch available | CNA |
- Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 VendorMicrosoft Affected 3.0.0.0 to before 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 Fixed in 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0 Patch available CNA
- Microsoft .NET Framework 3.5 AND 4.7.2 VendorMicrosoft Affected 4.7.0 to before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 Fixed in 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0 Patch available CNA
- Microsoft .NET Framework 3.5 AND 4.8 VendorMicrosoft Affected 4.8.0 to before 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 Fixed in 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0 Patch available CNA
- Microsoft .NET Framework 3.5 AND 4.8.1 VendorMicrosoft Affected 4.8.1 to before 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 Fixed in 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0 Patch available CNA
- Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 VendorMicrosoft Affected 4.7.0 to before 4.7.4150.0 Fixed in 4.7.4150.0 Patch available CNA
- Microsoft .NET Framework 4.8 VendorMicrosoft Affected 4.8.0 to before 4.8.4811.0 Fixed in 4.8.4811.0 Patch available CNA
- Microsoft .NET Framework 4.8.1 VendorMicrosoft Affected 4.8.0.0 to before 4.8.9363.0 Fixed in 4.8.9363.0 Patch available CNA
Remediation
Install the fixed builds for each product: 3.5 with 4.6.2/4.7/4.7.1/4.7.2 at 2.0.50727.8987, 3.0.30729.8982 and 4.7.4150.0; 3.5 with 4.7.2 at 2.0.50727.9073, 3.0.30729.9070 and 4.7.4150.0; 3.5 with 4.8 at 2.0.50727.9073, 3.0.30729.9070 and 4.8.4811.0; 3.5 with 4.8.1 at 2.0.50727.9188, 3.0.30729.9171 and 4.8.9363.0; 4.6.2/4.7/4.7.1/4.7.2 at 4.7.4150.0; 4.8 at 4.8.4811.0; and 4.8.1 at 4.8.9363.0.
Written with Claude Haiku 5.5 from the sources below · 2026-10-28
- Fix · CNA Microsoft .NET Framework 3.5 AND 4.6.2/4.7/4.7.1/4.7.2 (Microsoft) Fixed in 2.0.50727.8987 AND 3.0.30729.8982 AND 4.7.4150.0
- Fix · CNA Microsoft .NET Framework 3.5 AND 4.7.2 (Microsoft) Fixed in 2.0.50727.9073 AND 3.0.30729.9070 AND 4.7.4150.0
- Fix · CNA Microsoft .NET Framework 3.5 AND 4.8 (Microsoft) Fixed in 2.0.50727.9073 AND 3.0.30729.9070 AND 4.8.4811.0
- Fix · CNA Microsoft .NET Framework 3.5 AND 4.8.1 (Microsoft) Fixed in 2.0.50727.9188 AND 3.0.30729.9171 AND 4.8.9363.0
- Fix · CNA Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2 (Microsoft) Fixed in 4.7.4150.0
- Fix · CNA Microsoft .NET Framework 4.8 (Microsoft) Fixed in 4.8.4811.0
- Fix · CNA Microsoft .NET Framework 4.8.1 (Microsoft) Fixed in 4.8.9363.0
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
Not affected: 1 product
- Red Hat Hardened Images
Timeline
- 2026-10-13 Threatist record created from CVE-2026-108398
- 2026-10-13 CISA SSVC decision points changed
- 2026-10-13 Priority changed: MEDIUM → LOW
- 2026-10-13 Alias added: GHSA-895h-jx6m-8rp6
- 2026-10-14 Priority changed: LOW → MEDIUM
- 2026-10-23 Affected versions changed · Red Hat
- 2026-10-24 CVSS score added · Red Hat
- 2026-10-25 EPSS moved to the 50th–90th percentile
References
More Microsoft vulnerabilities
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- TI-2026-16982 Microsoft SharePoint Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-36863 Windows Server Update Service (WSUS) Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
- TI-2025-33671 Microsoft SharePoint Server Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
Sources
- CVE-2026-108398 · CVE Program
- CVE-2026-108398 · NVD
- FIRST EPSS
- GHSA-895h-jx6m-8rp6 · GitHub Advisory Database · CC BY 4.0
- CVE-2026-108398 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences