CVE-2026-35433

Description

Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally.

CVSS Details

CVSS Score

7.3

Severity

HIGH

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L

Configurations (Affected Products)

No configuration data available.

Microsoft .NET (具体受影响版本请参考官方安全公告)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

/*
 * PoC for CVE-2026-35433
 * This is a simulated demonstration of improper input validation leading to local privilege escalation.
 * Compile with: csc PoC.cs
 */
using System;
using System.Diagnostics;
using System.IO;

namespace PoC_CVE_2026_35433
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("[*] PoC Trigger for CVE-2026-35433: .NET Local Privilege Escalation");
            
            // Simulate malicious input that bypasses validation
            string maliciousInput = "..\..\Windows\System32\cmd.exe /c whoami";
            
            try
            {
                // Vulnerable function call simulating the lack of input sanitization
                ProcessVulnerableInput(maliciousInput);
            }
            catch (Exception ex)
            {
                Console.WriteLine("[-] Exploit failed: " + ex.Message);
            }
        }

        // Simulates a vulnerable .NET method handling file paths or commands
        static void ProcessVulnerableInput(string input)
        {
            Console.WriteLine("[+] Processing input: " + input);
            
            // In a real scenario, this might trigger a command injection or path traversal
            // leading to code execution with elevated privileges.
            ProcessStartInfo startInfo = new ProcessStartInfo();
            startInfo.FileName = "cmd.exe";
            startInfo.Arguments = "/c echo Vulnerable execution & " + input;
            startInfo.UseShellExecute = false;
            startInfo.RedirectStandardOutput = true;
            
            using (Process process = Process.Start(startInfo))
            {
                using (StreamReader reader = process.StandardOutput)
                {
                    string result = reader.ReadToEnd();
                    Console.WriteLine(result);
                }
            }
            
            Console.WriteLine("[+] Exploit execution finished.");
        }
    }
}

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-35433
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-35433
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-35433/
[4] VulDB https://vuldb.com/cve/CVE-2026-35433
[5] https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-35433

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-35433", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:13.710", "lastModified": "2026-05-13T15:34:52.573", "vulnStatus": "Awaiting Analysis", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper input validation in .NET allows an unauthorized attacker to elevate privileges locally."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:L", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.8, "impactScore": 5.5}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-20"}, {"lang": "en", "value": "CWE-190"}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-35433", "source": "[email protected]"}]}}