{
  "$ref": "https://www.cert.ssi.gouv.fr/openapi.json",
  "affected_systems": [
    {
      "description": "ASP.NET Core 10.0 versions ant\u00e9rieures \u00e0 10.0.7",
      "product": {
        "name": ".Net",
        "vendor": {
          "name": "Microsoft",
          "scada": false
        }
      }
    }
  ],
  "affected_systems_content": "",
  "content": "## Solutions\n\nSe r\u00e9f\u00e9rer au bulletin de s\u00e9curit\u00e9 de l\u0027\u00e9diteur pour l\u0027obtention des correctifs (cf. section Documentation).",
  "cves": [
    {
      "name": "CVE-2026-40372",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-40372"
    }
  ],
  "initial_release_date": "2026-04-22T00:00:00",
  "last_revision_date": "2026-04-22T00:00:00",
  "links": [],
  "reference": "CERTFR-2026-AVI-0478",
  "revisions": [
    {
      "description": "Version initiale",
      "revision_date": "2026-04-22T00:00:00.000000"
    }
  ],
  "risks": [
    {
      "description": "\u00c9l\u00e9vation de privil\u00e8ges"
    }
  ],
  "summary": "Une vuln\u00e9rabilit\u00e9 a \u00e9t\u00e9 d\u00e9couverte dans Microsoft .Net. Elle permet \u00e0 un attaquant de provoquer une \u00e9l\u00e9vation de privil\u00e8ges.",
  "title": "Vuln\u00e9rabilit\u00e9 dans Microsoft .Net",
  "vendor_advisories": [
    {
      "published_at": "2026-04-21",
      "title": "Bulletin de s\u00e9curit\u00e9 Microsoft .Net CVE-2026-40372",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372"
    }
  ]
}

{
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              "version": "10.0",
              "versionType": "custom"
            }
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        {
          "product": "Microsoft Visual Studio 2026 version 18.5",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "18.5.2",
              "status": "affected",
              "version": "18.5.0",
              "versionType": "custom"
            }
          ]
        }
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      "source": "secure@microsoft.com"
    },
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      "affectedData": [
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          "defaultStatus": "unaffected",
          "product": "Red Hat Enterprise Linux 10",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:8"
          ],
          "defaultStatus": "unaffected",
          "product": "Red Hat Enterprise Linux 8",
          "vendor": "Red Hat"
        },
        {
          "cpes": [
            "cpe:/o:redhat:enterprise_linux:9"
          ],
          "defaultStatus": "unaffected",
          "product": "Red Hat Enterprise Linux 9",
          "vendor": "Red Hat"
        }
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      "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
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              "versionEndExcluding": "10.0.7",
              "versionStartIncluding": "10.0.0",
              "vulnerable": true
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          ],
          "negate": false,
          "operator": "OR"
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    }
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Improper verification of cryptographic signature in ASP.NET Core allows an unauthorized attacker to elevate privileges over a network."
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  "lastModified": "2026-06-27T05:16:44.510",
  "metrics": {
    "cvssMetricV31": [
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          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
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        "source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
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          "role": "CISA Coordinator",
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  "published": "2026-04-21T20:16:59.133",
  "references": [
    {
      "source": "secure@microsoft.com",
      "tags": [
        "Vendor Advisory"
      ],
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 10.0.6"
      },
      "package": {
        "ecosystem": "NuGet",
        "name": "Microsoft.AspNetCore.DataProtection"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "10.0.0"
            },
            {
              "fixed": "10.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-40372"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-347"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-23T14:55:41Z",
    "nvd_published_at": "2026-04-21T20:16:59Z",
    "severity": "CRITICAL"
  },
  "details": "## Executive Summary: \n\nA bug in `Microsoft.AspNetCore.DataProtection` 10.0.0-10.0.6 NuGet packages can give an attacker the opportunity to execute an Elevation of Privilege attack by forging authentication cookies, and also allows some protected payloads to be decrypted.\n\nIf an attacker used forged payloads to authenticate as a privileged user during the vulnerable window, they may have induced the application to issue **legitimately-signed** tokens (session refresh, API key, password reset link, etc.) to themselves. Those tokens remain valid after upgrading to 10.0.7 unless the DataProtection key ring is rotated.\n\nThis is comparable in capability to [MS10-070](https://learn.microsoft.com/en-us/security-updates/SecurityBulletins/2010/ms10-070), which exploited a similar padding-oracle condition in ASP.NET\u0027s legacy encryption infrastructure.\n\n## Announcement\n\nAnnouncement for this issue can be found at https://github.com/dotnet/announcements/issues/395\n\n## CVSS Details\n\n- **Version:** 3.1\n- **Severity:** Important\n- **Score:** 9.1\n- **Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N\n- **Weakness:** CWE-347: Improper Verification of Cryptographic Signature\n\n## Affected Platforms\n\n- **Platforms:** All\n- **Architectures:** All\n\n## \u003ca name=\"affected-packages\"\u003e\u003c/a\u003eAffected Packages\nThe vulnerability affects some Microsoft .NET projects if they use any of affected package versions listed below\n\n### \u003ca name=\"ASP.NET Core 10\"\u003e\u003c/a\u003eASP.NET Core 10\nPackage name | Affected version | Patched version\n------------ | ---------------- | -------------------------\n[Microsoft.AspNetCore.DataProtection](https://www.nuget.org/packages/Microsoft.AspNetCore.DataProtection)               | \u003e=10.0.0, \u003c=10.0.6 | 10.0.7\n\n## Advisory FAQ\n\n### \u003ca name=\"how-affected\"\u003e\u003c/a\u003eHow do I know if I am affected?\n \n#### Primary affected configuration (10.0.6 on `net10.0`)\n \nYou are **affected** if ALL of the following are true:\n \n- Your application referenced `Microsoft.AspNetCore.DataProtection` version 10.0.6 from NuGet (directly or transitively via, e.g., `Microsoft.AspNetCore.DataProtection.StackExchangeRedis`, `.EntityFrameworkCore`, `.AzureKeyVault`, `.AzureStorage`, `.Redis`), AND\nThe affected 10.0.6 NuGet binary was actually loaded at runtime. This happens when either the application does NOT target the Microsoft.NET.Sdk.Web NOR has a Microsoft.AspNetCore.App framework reference either directly or transitively UNLESS you opt out of PrunePackageReference which is enabled by default in .NET 10. \n- The application ran on Linux, macOS, or any non-Windows operating system.\n \n#### Secondary affected configuration (10.0.x on `net462` / `netstandard2.0`)\n\nYou are also affected if:\n \n- Your application or library referenced `Microsoft.AspNetCore.DataProtection` versions 10.0.0 through 10.0.6 from NuGet, AND\n- The build consumed the `net462` or `netstandard2.0` target framework asset of that package. This occurs when your application does not target `net10.0` and consumes the package (e.g. `net8.0`, `net9.0`, `net481` for mono, etc.). This combination is unusual because 10.0 NuGet packages are generally intended for use with .NET 10.\n \nThis secondary population is much smaller and is expected to primarily consist of:\n- Desktop or server applications on .NET Framework that happen to use the ASP.NET Core DataProtection NuGet package.\n- Libraries that target `netstandard2.0` and reference the 10.0 DataProtection package.\n \nThese configurations use the same managed authenticated encryptor code path on all operating systems (the CNG path is only available on the `net10.0` asset), so the Windows exception below does not apply to them.\n \n#### Not affected\n \n- Your application runs on **Windows** \n- Your application runs **framework-dependent** on `net10.0` and your installed ASP.NET Core shared framework version is **\u2265** your PackageReference version of `Microsoft.AspNetCore.DataProtection`. In this case the (correct) shared framework copy is loaded and the NuGet copy is not used. For example, shared framework 10.0.6 + PackageReference 10.0.6 is safe; shared framework 10.0.5 + PackageReference 10.0.6 is not.\n- Your application uses `Microsoft.AspNetCore.DataProtection` **8.0.x or 9.0.x** from NuGet, on any target framework, any operating system, any shared framework version. The defective code path was introduced during 10.0 development and was never backported to the 8.0 or 9.0 servicing branches.\n- Your application never referenced any affected version of the package.\n\n### \u003ca name=\"how-fix\"\u003e\u003c/a\u003eHow do I fix the issue?\n\n1. **Upgrade `Microsoft.AspNetCore.DataProtection` to 10.0.7 or later** and redeploy. This fixes the validation routine. Any forged payloads produced during the vulnerable window (which necessarily carried all-zero HMAC bytes) will be rejected by the corrected code.\n \n2. **Rotate the DataProtection key ring** if your application was affected and served internet-exposed endpoints during the vulnerable window. This invalidates any legitimately-signed tokens the application may have issued to attackers during that period.\n \n   Example using the built-in key manager:\n \n   ```csharp\n   // Run once, from an application with access to the same key ring.\n   // Replace the cutoff with a timestamp just before you deployed 10.0.6.\n   var services = new ServiceCollection()\n       .AddDataProtection()\n       // ... your existing repository / protection configuration ...\n       .Services\n       .BuildServiceProvider();\n \n   var keyManager = services.GetRequiredService\u003cIKeyManager\u003e();\n   keyManager.RevokeAllKeys(\n       revocationDate: DateTimeOffset.UtcNow,      // revoke all keys currently in the ring\n       reason: \"CVE-TBD: DataProtection 10.0.6 validation bypass\");\n   ```\n \n   `RevokeAllKeys` marks every existing key as revoked; a new key is auto-generated on the next protect operation. All users will need to sign in again, all antiforgery tokens will be reissued, etc.\n \n   If you can be more surgical \u2014 for instance, you know no key older than `T` was used by an affected process \u2014 use `RevokeKey(Guid keyId, string reason)` instead to revoke only the keys that were active during the vulnerable window.\n \n3. **Audit application-level long-lived artifacts** that were created during the vulnerable window and carry identity or capability. These survive key rotation and must be rotated at the application layer:\n   - API keys, refresh tokens, or access tokens stored in your database and issued via a protected endpoint.\n   - Password reset links or email-confirmation tokens that were emitted during the window and have not yet expired.\n   - Any other persistent capability that an authenticated request could have caused your application to issue.\n \n   If your application does not issue such long-lived artifacts via authenticated endpoints, key rotation alone is sufficient.\n \n### Recommended\n \n4. **Audit plaintext stored inside protected payloads.** If your application stores long-lived secrets (database connection strings, third-party API keys, etc.) inside `IDataProtector.Protect` output, treat those secrets as potentially disclosed and rotate them at their respective sources.\n \n5. **Review web server logs** for anomalous request volume against endpoints that accept protected payloads (auth cookies, antiforgery tokens, state parameters). The padding-oracle attack requires many requests per byte recovered \u2014 orders of magnitude more than normal traffic for that endpoint. Sustained high-volume traffic with varying cookie/query-parameter values against a single authenticated endpoint during the vulnerable window is a strong indicator.\n\n## Other Information\n\n### Reporting Security Issues\n\nIf you have found a potential security issue in a supported version of .NET, please report it to the Microsoft Security Response Center (MSRC) via the [MSRC Researcher Portal](https://msrc.microsoft.com/report/vulnerability/new). Further information can be found in the MSRC [Report an Issue FAQ](https://www.microsoft.com/msrc/faqs-report-an-issue).\n\nSecurity reports made through MSRC may qualify for the Microsoft .NET Bounty. Details of the Microsoft .NET Bounty Program including terms and conditions are at https://aka.ms/corebounty.\n\n### Support\n\nYou can ask questions about this issue on GitHub in the .NET GitHub organization. The main ASP.NET Core repo is located at https://github.com/dotnet/aspnetcore. The Announcements repo (https://github.com/dotnet/Announcements) will contain this bulletin as an issue and will include a link to a discussion issue. You can ask questions in the linked discussion issue.\n\n### Disclaimer\n\nThe information provided in this advisory is provided \"as is\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.\n\n### External Links\n\n[CVE-2026-40372]( https://www.cve.org/CVERecord?id=CVE-2026-40372)\n\n### Revisions\n\nV1.0 (April 21, 2026): Advisory published.",
  "id": "GHSA-9mv3-2cwr-p262",
  "modified": "2026-04-24T19:59:43Z",
  "published": "2026-04-23T14:55:41Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/dotnet/aspnetcore/security/advisories/GHSA-9mv3-2cwr-p262"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-40372"
    },
    {
      "type": "WEB",
      "url": "https://github.com/dotnet/announcements/issues/395"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/dotnet/aspnetcore"
    },
    {
      "type": "WEB",
      "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Microsoft Security Advisory CVE-2026-40372 \u2013 ASP.NET Core Elevation of Privilege"
}

{
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        "title": "Additional Resources"
      },
      {
        "category": "legal_disclaimer",
        "text": "The information provided in the Microsoft Knowledge Base is provided \\\"as is\\\" without warranty of any kind. Microsoft disclaims all warranties, either express or implied, including the warranties of merchantability and fitness for a particular purpose. In no event shall Microsoft Corporation or its suppliers be liable for any damages whatsoever including direct, indirect, incidental, consequential, loss of business profits or special damages, even if Microsoft Corporation or its suppliers have been advised of the possibility of such damages. Some states do not allow the exclusion or limitation of liability for consequential or incidental damages so the foregoing limitation may not apply.",
        "title": "Disclaimer"
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        "text": "Required. The vulnerability documented by this CVE requires customer action to resolve.",
        "title": "Customer Action"
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      {
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        "summary": "Microsoft Support Lifecycle",
        "url": "https://support.microsoft.com/lifecycle"
      },
      {
        "category": "external",
        "summary": "Common Vulnerability Scoring System",
        "url": "https://www.first.org/cvss"
      }
    ],
    "title": "ASP.NET Core Elevation of Privilege Vulnerability",
    "tracking": {
      "current_release_date": "2026-04-28T07:00:00.000Z",
      "generator": {
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        {
          "category": "general",
          "text": "Microsoft",
          "title": "Assigning CNA"
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        {
          "category": "faq",
          "text": "An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.",
          "title": "What privileges could be gained by an attacker who successfully exploited this vulnerability?"
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        {
          "category": "faq",
          "text": "You are affected if all three of the following are true:\nYour application uses Microsoft.AspNetCore.DataProtection 10.0.6 from NuGet (directly, or through a package that depends on it such as Microsoft.AspNetCore.DataProtection.StackExchangeRedis).\nThe NuGet copy of the library was actually loaded at runtime \u2014 not the shared framework copy. This typically means you deploy self-contained, or your installed shared framework is older than the NuGet package version.\nYour application runs on Linux, macOS, or another non-Windows OS.\nHow do I determine if the vulnerable binary was loaded?\nCheck application logs. The clearest symptom is users being logged out and repeated \u0026quot;The payload was invalid\u0026quot; errors in your logs after upgrading to 10.0.6.\nCheck your project file. Look for a PackageReference to Microsoft.AspNetCore.DataProtection version 10.0.6 in your .csproj file (or in a package that depends on it). You can also run dotnet list package to see resolved package versions.\nInspect the binary on disk. See [https://file+.vscode-resource.vscode-cdn.net/c%3A/Users/shalter/Downloads/advisory-upd-1.md#technical-details]Technical details for how to distinguish the affected NuGet binary from the correct shared framework binary by file size.\nShared framework deployments are not affected. If your application runs framework-dependent and the installed ASP.NET Core shared framework version is \u2265 your Microsoft.AspNetCore.DataProtection PackageReference version, the correct shared framework binary is loaded and the NuGet binary is never used.\nWindows deployments are not affected. On Windows, DataProtection uses CNG-based encryptors by default, which do not contain this bug. 8.0.x and 9.0.x packages are not affected. The defective code path was introduced during 10.0 development and was never backported.\nWindows with managed algorithms: If you run on Windows but explicitly opted into managed algorithms via UseCustomCryptographicAlgorithms, you are also affected.\nOlder target frameworks: A smaller population running net462 / netstandard2.0 with Microsoft.AspNetCore.DataProtection 10.0.0\u201310.0.6 is affected on all operating systems. See [https://file+.vscode-resource.vscode-cdn.net/c%3A/Users/shalter/Downloads/advisory-upd-1.md#technical-details]Technical details for specifics.\nhttps://github.com/dotnet/announcements/issues/395",
          "title": "How do I know if I\u0027m affected?"
        },
        {
          "category": "faq",
          "text": "Exploiting this vulnerability could allow an attacker to disclose files and modify data, but the attacker cannot impact the availability of the system.",
          "title": "According to the CVSS metrics, successful exploitation of this vulnerability could lead to major loss of confidentiality (C:H), and integrity (I:H), but could lead to no loss of availability (A:N). What does that mean for this vulnerability?"
        }
      ],
      "product_status": {
        "fixed": [
          "20932",
          "21244"
        ],
        "known_affected": [
          "1",
          "2"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-40372 ASP.NET Core Elevation of Privilege Vulnerability - HTML",
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372"
        },
        {
          "category": "self",
          "summary": "CVE-2026-40372 ASP.NET Core Elevation of Privilege Vulnerability - CSAF",
          "url": "https://msrc.microsoft.com/csaf/advisories/2026/msrc_cve-2026-40372.json"
        }
      ],
      "remediations": [
        {
          "category": "vendor_fix",
          "date": "2026-04-21T07:00:00.000Z",
          "details": "10.0.7:Security Update:https://support.microsoft.com/help/5091596",
          "product_ids": [
            "2"
          ],
          "url": "https://support.microsoft.com/help/5091596"
        },
        {
          "category": "vendor_fix",
          "date": "2026-04-21T07:00:00.000Z",
          "details": "18.5.2:Security Update:https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes",
          "product_ids": [
            "1"
          ],
          "url": "https://learn.microsoft.com/en-us/visualstudio/releases/2026/release-notes"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "confidentialityImpact": "HIGH",
            "environmentalsScore": 0.0,
            "exploitCodeMaturity": "UNPROVEN",
            "integrityImpact": "HIGH",
            "privilegesRequired": "NONE",
            "remediationLevel": "OFFICIAL_FIX",
            "reportConfidence": "CONFIRMED",
            "scope": "UNCHANGED",
            "temporalScore": 7.9,
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "1",
            "2"
          ]
        }
      ],
      "threats": [
        {
          "category": "impact",
          "details": "Elevation of Privilege"
        },
        {
          "category": "exploit_status",
          "details": "Publicly Disclosed:No;Exploited:No;Latest Software Release:Exploitation Less Likely"
        }
      ],
      "title": "ASP.NET Core Elevation of Privilege Vulnerability"
    }
  ]
}

{
  "document": {
    "category": "csaf_security_advisory",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE"
      }
    },
    "lang": "nl",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this page to enhance access to its information and security advisories. The use of this security advisory is subject to the following terms and conditions:\n\n    NCSC-NL makes every reasonable effort to ensure that the content of this page is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or continuous keeping up-to-date. The information contained in this security advisory is intended solely for the purpose of providing general information to professional users. No rights can be derived from the information provided therein.\n\n    NCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of this security advisory. This includes damage resulting from the inaccuracy of incompleteness of the information contained in the advisory.\n    This security advisory is subject to Dutch law. All disputes related to or arising from the use of this advisory will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings."
      },
      {
        "category": "description",
        "text": "Microsoft heeft een kwetsbaarheid verholpen in ASP.NET Core.",
        "title": "Feiten"
      },
      {
        "category": "description",
        "text": "De kwetsbaarheid ontstaat door onjuiste verificatie van cryptografische handtekeningen binnen ASP.NET Core. Hierdoor kan een onbevoegde aanvaller binnen een netwerk privileges verhogen door beveiligingscontroles te omzeilen en ongeautoriseerde toegang met verhoogde rechten te verkrijgen.",
        "title": "Interpretaties"
      },
      {
        "category": "description",
        "text": "Microsoft heeft een update uitgebracht om de kwetsbaarheid te verhelpen. Zie bijgevoegde referenties voor meer informatie.",
        "title": "Oplossingen"
      },
      {
        "category": "general",
        "text": "medium",
        "title": "Kans"
      },
      {
        "category": "general",
        "text": "high",
        "title": "Schade"
      },
      {
        "category": "general",
        "text": "Improper Verification of Cryptographic Signature",
        "title": "CWE-347"
      }
    ],
    "publisher": {
      "category": "coordinator",
      "contact_details": "cert@ncsc.nl",
      "name": "Nationaal Cyber Security Centrum",
      "namespace": "https://www.ncsc.nl/"
    },
    "references": [
      {
        "category": "external",
        "summary": "Reference",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372"
      }
    ],
    "title": "Kwetsbaarheid verholpen in ASP.NET Core van Microsoft",
    "tracking": {
      "current_release_date": "2026-04-22T09:40:27.334869Z",
      "generator": {
        "date": "2025-08-04T16:30:00Z",
        "engine": {
          "name": "V.A.",
          "version": "1.3"
        }
      },
      "id": "NCSC-2026-0123",
      "initial_release_date": "2026-04-22T09:40:27.334869Z",
      "revision_history": [
        {
          "date": "2026-04-22T09:40:27.334869Z",
          "number": "1.0.0",
          "summary": "Initiele versie"
        }
      ],
      "status": "final",
      "version": "1.0.0"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "vers:unknown/*",
                "product": {
                  "name": "vers:unknown/*",
                  "product_id": "CSAFPID-1"
                }
              }
            ],
            "category": "product_name",
            "name": "ASP.NET Core 10.0"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-40372",
      "cwe": {
        "id": "CWE-347",
        "name": "Improper Verification of Cryptographic Signature"
      },
      "notes": [
        {
          "category": "other",
          "text": "Improper Verification of Cryptographic Signature",
          "title": "CWE-347"
        },
        {
          "category": "description",
          "text": "An improper verification of cryptographic signatures in ASP.NET Core allows unauthorized attackers to remotely elevate privileges by exploiting signature validation flaws.",
          "title": "Summary"
        }
      ],
      "product_status": {
        "known_affected": [
          "CSAFPID-1"
        ]
      },
      "references": [
        {
          "category": "self",
          "summary": "CVE-2026-40372 | NCSC-NL Website",
          "url": "https://vulnerabilities.ncsc.nl/csaf/v2/2026/cve-2026-40372.json"
        }
      ],
      "scores": [
        {
          "cvss_v3": {
            "baseScore": 9.1,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "products": [
            "CSAFPID-1"
          ]
        }
      ],
      "title": "CVE-2026-40372"
    }
  ]
}

{
  "document": {
    "aggregate_severity": {
      "text": "hoch"
    },
    "category": "csaf_base",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "de-DE",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
      },
      {
        "category": "description",
        "text": "Microsoft ASP.NET (Active Server Pages .NET) ist eine Technologie zum Erstellen dynamischer Webseiten, Webanwendungen und Webservices auf Basis des Microsoft .NET-Frameworks.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Microsoft ASP.NET ausnutzen, um seine Privilegien zu erh\u00f6hen.",
        "title": "Angriff"
      },
      {
        "category": "general",
        "text": "- Windows",
        "title": "Betroffene Betriebssysteme"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "csaf-provider@cert-bund.de",
      "name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
      "namespace": "https://www.bsi.bund.de"
    },
    "references": [
      {
        "category": "self",
        "summary": "WID-SEC-W-2026-1213 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-1213.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2026-1213 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2026-1213"
      },
      {
        "category": "external",
        "summary": "Microsoft Security Advisory vom 2026-04-21",
        "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-40372"
      },
      {
        "category": "external",
        "summary": "GitHub Issue vom 2026-04-21",
        "url": "https://github.com/dotnet/announcements/issues/395"
      },
      {
        "category": "external",
        "summary": "Ubuntu Security Notice USN-8215-1 vom 2026-04-28",
        "url": "https://ubuntu.com/security/notices/USN-8215-1"
      },
      {
        "category": "external",
        "summary": "Ubuntu Security Notice USN-8216-1 vom 2026-04-28",
        "url": "https://ubuntu.com/security/notices/USN-8216-1"
      },
      {
        "category": "external",
        "summary": "Fedora Security Advisory FEDORA-2026-32952BABA5 vom 2026-05-02",
        "url": "https://bodhi.fedoraproject.org/updates/FEDORA-2026-32952baba5"
      },
      {
        "category": "external",
        "summary": "Fedora Security Advisory FEDORA-2026-018D6721A0 vom 2026-05-02",
        "url": "https://bodhi.fedoraproject.org/updates/FEDORA-2026-018d6721a0"
      },
      {
        "category": "external",
        "summary": "Fedora Security Advisory FEDORA-2026-BE6EA464D0 vom 2026-05-02",
        "url": "https://bodhi.fedoraproject.org/updates/FEDORA-2026-be6ea464d0"
      }
    ],
    "source_lang": "en-US",
    "title": "Microsoft ASP.NET: Schwachstelle erm\u00f6glicht Privilegieneskalation",
    "tracking": {
      "current_release_date": "2026-05-03T22:00:00.000+00:00",
      "generator": {
        "date": "2026-05-04T09:36:07.650+00:00",
        "engine": {
          "name": "BSI-WID",
          "version": "1.5.0"
        }
      },
      "id": "WID-SEC-W-2026-1213",
      "initial_release_date": "2026-04-21T22:00:00.000+00:00",
      "revision_history": [
        {
          "date": "2026-04-21T22:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        },
        {
          "date": "2026-04-28T22:00:00.000+00:00",
          "number": "2",
          "summary": "Neue Updates von Ubuntu aufgenommen"
        },
        {
          "date": "2026-05-03T22:00:00.000+00:00",
          "number": "3",
          "summary": "Neue Updates von Fedora aufgenommen"
        }
      ],
      "status": "final",
      "version": "3"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "category": "product_name",
            "name": "Fedora Linux",
            "product": {
              "name": "Fedora Linux",
              "product_id": "74185",
              "product_identification_helper": {
                "cpe": "cpe:/o:fedoraproject:fedora:-"
              }
            }
          }
        ],
        "category": "vendor",
        "name": "Fedora"
      },
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c10.0.7",
                "product": {
                  "name": "Microsoft ASP.NET \u003c10.0.7",
                  "product_id": "T053165"
                }
              },
              {
                "category": "product_version",
                "name": "10.0.7",
                "product": {
                  "name": "Microsoft ASP.NET 10.0.7",
                  "product_id": "T053165-fixed",
                  "product_identification_helper": {
                    "cpe": "cpe:/a:microsoft:asp.net:10.0.7"
                  }
                }
              }
            ],
            "category": "product_name",
            "name": "ASP.NET"
          }
        ],
        "category": "vendor",
        "name": "Microsoft"
      },
      {
        "branches": [
          {
            "category": "product_name",
            "name": "Ubuntu Linux",
            "product": {
              "name": "Ubuntu Linux",
              "product_id": "T000126",
              "product_identification_helper": {
                "cpe": "cpe:/o:canonical:ubuntu_linux:-"
              }
            }
          }
        ],
        "category": "vendor",
        "name": "Ubuntu"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2026-40372",
      "product_status": {
        "known_affected": [
          "T053165",
          "T000126",
          "74185"
        ]
      },
      "release_date": "2026-04-21T22:00:00.000+00:00",
      "title": "CVE-2026-40372"
    }
  ]
}