Common Weakness Enumeration

CWE-434

Allowed

Unrestricted Upload of File with Dangerous Type

Abstraction: Base · Status: Draft

API response cwe.mitre.org

The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.

5971 vulnerabilities reference this CWE, most recent first.

GHSA-PCWJ-HP7W-9PPV

Vulnerability from github – Published: 2022-05-24 16:49 – Updated: 2023-02-03 21:30
VLAI
Details

IBM Security Guardium 10.5 could allow a remote attacker to upload arbitrary files, which could allow the attacker to execute arbitrary code on the vulnerable web server. IBM X-Force ID: 160698.

Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2019-4292"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-07-02T15:15:00Z",
    "severity": "HIGH"
  },
  "details": "IBM Security Guardium 10.5 could allow a remote attacker to upload arbitrary files, which could allow the attacker to execute arbitrary code on the vulnerable web server. IBM X-Force ID: 160698.",
  "id": "GHSA-pcwj-hp7w-9ppv",
  "modified": "2023-02-03T21:30:29Z",
  "published": "2022-05-24T16:49:17Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-4292"
    },
    {
      "type": "WEB",
      "url": "https://exchange.xforce.ibmcloud.com/vulnerabilities/160698"
    },
    {
      "type": "WEB",
      "url": "https://www.ibm.com/support/docview.wss?uid=ibm10888279"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/109005"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-PF3Q-84PR-FV6P

Vulnerability from github – Published: 2022-05-24 22:28 – Updated: 2022-05-24 22:28
VLAI
Details

Thrive “Legacy” Rise by Thrive Themes WordPress theme before 2.0.0, Luxe by Thrive Themes WordPress theme before 2.0.0, Minus by Thrive Themes WordPress theme before 2.0.0, Ignition by Thrive Themes WordPress theme before 2.0.0, FocusBlog by Thrive Themes WordPress theme before 2.0.0, Squared by Thrive Themes WordPress theme before 2.0.0, Voice WordPress theme before 2.0.0, Performag by Thrive Themes WordPress theme before 2.0.0, Pressive by Thrive Themes WordPress theme before 2.0.0, Storied by Thrive Themes WordPress theme before 2.0.0 register a REST API endpoint to compress images using the Kraken image optimization engine. By supplying a crafted request in combination with data inserted using the Option Update vulnerability, it was possible to use this endpoint to retrieve malicious code from a remote URL and overwrite an existing file on the site with it or create a new file.This includes executable PHP files that contain malicious code.

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{
  "affected": [],
  "aliases": [
    "CVE-2021-24220"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-04-12T14:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Thrive \u201cLegacy\u201d Rise by Thrive Themes WordPress theme before 2.0.0, Luxe by Thrive Themes WordPress theme before 2.0.0, Minus by Thrive Themes WordPress theme before 2.0.0, Ignition by Thrive Themes WordPress theme before 2.0.0, FocusBlog by Thrive Themes WordPress theme before 2.0.0, Squared by Thrive Themes WordPress theme before 2.0.0, Voice WordPress theme before 2.0.0, Performag by Thrive Themes WordPress theme before 2.0.0, Pressive by Thrive Themes WordPress theme before 2.0.0, Storied by Thrive Themes WordPress theme before 2.0.0 register a REST API endpoint to compress images using the Kraken image optimization engine. By supplying a crafted request in combination with data inserted using the Option Update vulnerability, it was possible to use this endpoint to retrieve malicious code from a remote URL and overwrite an existing file on the site with it or create a new file.This includes executable PHP files that contain malicious code.",
  "id": "GHSA-pf3q-84pr-fv6p",
  "modified": "2022-05-24T22:28:50Z",
  "published": "2022-05-24T22:28:50Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-24220"
    },
    {
      "type": "WEB",
      "url": "https://wpscan.com/vulnerability/a2424354-2639-4f53-a24f-afc11f6c4cac"
    },
    {
      "type": "WEB",
      "url": "https://www.wordfence.com/blog/2021/03/recently-patched-vulnerability-in-thrive-themes-actively-exploited-in-the-wild"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-PF64-5XCW-6787

Vulnerability from github – Published: 2026-06-17 18:35 – Updated: 2026-06-17 18:35
VLAI
Details

Unrestricted Upload of File with Dangerous Type vulnerability in Kodezen LLC Academy LMS Pro allows Upload a Web Shell to a Web Server.

This issue affects Academy LMS Pro: from n/a before 3.5.2.

Severity
8.0 (High)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2026-39598"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-06-17T13:20:22Z",
    "severity": "HIGH"
  },
  "details": "Unrestricted Upload of File with Dangerous Type vulnerability in Kodezen LLC Academy LMS Pro allows Upload a Web Shell to a Web Server.\n\nThis issue affects Academy LMS Pro: from n/a before 3.5.2.",
  "id": "GHSA-pf64-5xcw-6787",
  "modified": "2026-06-17T18:35:49Z",
  "published": "2026-06-17T18:35:49Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39598"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/plugin/academy-pro/vulnerability/wordpress-academy-lms-pro-plugin-3-5-2-arbitrary-file-upload-vulnerability?_s_id=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-PF6C-6JFW-4CWC

Vulnerability from github – Published: 2021-12-01 00:00 – Updated: 2021-12-07 00:01
VLAI
Details

Zoho ManageEngine M365 Manager Plus before 4421 is vulnerable to file-upload remote code execution.

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{
  "affected": [],
  "aliases": [
    "CVE-2021-42099"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-11-30T19:15:00Z",
    "severity": "CRITICAL"
  },
  "details": "Zoho ManageEngine M365 Manager Plus before 4421 is vulnerable to file-upload remote code execution.",
  "id": "GHSA-pf6c-6jfw-4cwc",
  "modified": "2021-12-07T00:01:03Z",
  "published": "2021-12-01T00:00:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42099"
    },
    {
      "type": "WEB",
      "url": "https://www.manageengine.com"
    },
    {
      "type": "WEB",
      "url": "https://www.manageengine.com/microsoft-365-management-reporting/release-notes.html#4421"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-PF85-6VFC-9453

Vulnerability from github – Published: 2022-05-24 17:02 – Updated: 2024-04-04 02:41
VLAI
Details

BMC Smart Reporting 7.3 20180418 allows authenticated XXE within the import functionality. One can import a malicious XML file and perform XXE attacks to download local files from the server, or do DoS attacks with XML expansion attacks. XXE with direct response and XXE OOB are allowed.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2019-11216"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2019-12-04T20:15:00Z",
    "severity": "MODERATE"
  },
  "details": "BMC Smart Reporting 7.3 20180418 allows authenticated XXE within the import functionality. One can import a malicious XML file and perform XXE attacks to download local files from the server, or do DoS attacks with XML expansion attacks. XXE with direct response and XXE OOB are allowed.",
  "id": "GHSA-pf85-6vfc-9453",
  "modified": "2024-04-04T02:41:52Z",
  "published": "2022-05-24T17:02:39Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2019-11216"
    },
    {
      "type": "WEB",
      "url": "https://docs.bmc.com/docs/itsm90/export-and-import-repository-509983929.html"
    },
    {
      "type": "WEB",
      "url": "http://packetstormsecurity.com/files/155552/BMC-Smart-Reporting-7.3-20180418-XML-Injection.html"
    },
    {
      "type": "WEB",
      "url": "http://seclists.org/fulldisclosure/2019/Dec/7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-PF9P-78XV-V5R8

Vulnerability from github – Published: 2021-12-08 00:01 – Updated: 2021-12-09 00:01
VLAI
Details

An unrestricted file upload vulnerability exists in Ivanti Avalanche before 6.3.3 allows an attacker with access to the Inforail Service to write dangerous files.

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{
  "affected": [],
  "aliases": [
    "CVE-2021-42125"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-12-07T14:15:00Z",
    "severity": "HIGH"
  },
  "details": "An unrestricted file upload vulnerability exists in Ivanti Avalanche before 6.3.3 allows an attacker with access to the Inforail Service to write dangerous files.",
  "id": "GHSA-pf9p-78xv-v5r8",
  "modified": "2021-12-09T00:01:45Z",
  "published": "2021-12-08T00:01:35Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-42125"
    },
    {
      "type": "WEB",
      "url": "https://forums.ivanti.com/s/article/Security-Alert-CVE-s-Addressed-in-Avalanche-6-3-3"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-PFJ9-JRRX-G7R5

Vulnerability from github – Published: 2026-01-06 21:30 – Updated: 2026-04-28 21:35
VLAI
Details

Unrestricted Upload of File with Dangerous Type vulnerability in Themify Themify Sidepane WordPress Theme, Themify Themify Newsy, Themify Themify Folo, Themify Themify Edmin, Themify Bloggie, Themify Photobox, Themify Wigi, Themify Rezo, Themify Slide allows Upload a Web Shell to a Web Server.This issue affects Themify Sidepane WordPress Theme: from n/a through 1.9.8; Themify Newsy: from n/a through 1.9.9; Themify Folo: from n/a through 1.9.6; Themify Edmin: from n/a through 2.0.0; Bloggie: from n/a through 2.0.8; Photobox: from n/a through 2.0.1; Wigi: from n/a through 2.0.1; Rezo: from n/a through 1.9.7; Slide: from n/a through 1.7.5.

Severity
9.9 (Critical)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2025-30996"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-01-06T21:15:42Z",
    "severity": "CRITICAL"
  },
  "details": "Unrestricted Upload of File with Dangerous Type vulnerability in Themify Themify Sidepane WordPress Theme, Themify Themify Newsy, Themify Themify Folo, Themify Themify Edmin, Themify Bloggie, Themify Photobox, Themify Wigi, Themify Rezo, Themify Slide allows Upload a Web Shell to a Web Server.This issue affects Themify Sidepane WordPress Theme: from n/a through 1.9.8; Themify Newsy: from n/a through 1.9.9; Themify Folo: from n/a through 1.9.6; Themify Edmin: from n/a through 2.0.0; Bloggie: from n/a through 2.0.8; Photobox: from n/a through 2.0.1; Wigi: from n/a through 2.0.1; Rezo: from n/a through 1.9.7; Slide: from n/a through 1.7.5.",
  "id": "GHSA-pfj9-jrrx-g7r5",
  "modified": "2026-04-28T21:35:53Z",
  "published": "2026-01-06T21:30:34Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-30996"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/bloggie/vulnerability/wordpress-bloggie-2-0-8-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/edmin/vulnerability/wordpress-themify-edmin-2-0-0-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/folo/vulnerability/wordpress-themify-folo-1-9-6-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/newsy/vulnerability/wordpress-themify-newsy-1-9-9-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/photobox/vulnerability/wordpress-photobox-2-0-1-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/rezo/vulnerability/wordpress-rezo-1-9-7-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/sidepane/vulnerability/wordpress-themify-sidepane-wordpress-theme-1-9-8-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/slide/vulnerability/wordpress-slide-1-7-5-arbitrary-file-upload-vulnerability?_s_id=cve"
    },
    {
      "type": "WEB",
      "url": "https://patchstack.com/database/wordpress/theme/wigi/vulnerability/wordpress-wigi-2-0-1-arbitrary-file-upload-vulnerability?_s_id=cve"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-PFJC-CFQC-87F5

Vulnerability from github – Published: 2026-02-23 21:31 – Updated: 2026-02-23 21:31
VLAI
Details

A flaw has been found in ShuoRen Smart Heating Integrated Management Platform 1.0.0. Affected by this vulnerability is an unknown functionality of the file /MP/Service/Webservice/ExampleNodeService.asmx. Executing a manipulation of the argument File can lead to unrestricted upload. It is possible to launch the attack remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Severity
7.3 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
5.5 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P
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{
  "affected": [],
  "aliases": [
    "CVE-2026-3025"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-284",
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-02-23T21:19:12Z",
    "severity": "MODERATE"
  },
  "details": "A flaw has been found in ShuoRen Smart Heating Integrated Management Platform 1.0.0. Affected by this vulnerability is an unknown functionality of the file /MP/Service/Webservice/ExampleNodeService.asmx. Executing a manipulation of the argument File can lead to unrestricted upload. It is possible to launch the attack remotely. The exploit has been published and may be used. The vendor was contacted early about this disclosure but did not respond in any way.",
  "id": "GHSA-pfjc-cfqc-87f5",
  "modified": "2026-02-23T21:31:28Z",
  "published": "2026-02-23T21:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-3025"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?ctiid.347381"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?id.347381"
    },
    {
      "type": "WEB",
      "url": "https://vuldb.com/?submit.756376"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-PFQ6-6C5H-RM27

Vulnerability from github – Published: 2022-05-14 01:51 – Updated: 2022-05-14 01:51
VLAI
Details

Webiness Inventory 2.3 suffers from an Arbitrary File upload vulnerability via PHP code in the protected/library/ajax/WsSaveToModel.php logo parameter.

Severity
9.8 (Critical)
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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{
  "affected": [],
  "aliases": [
    "CVE-2018-18752"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2018-10-29T12:29:00Z",
    "severity": "CRITICAL"
  },
  "details": "Webiness Inventory 2.3 suffers from an Arbitrary File upload vulnerability via PHP code in the protected/library/ajax/WsSaveToModel.php logo parameter.",
  "id": "GHSA-pfq6-6c5h-rm27",
  "modified": "2022-05-14T01:51:58Z",
  "published": "2022-05-14T01:51:58Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2018-18752"
    },
    {
      "type": "WEB",
      "url": "https://packetstormsecurity.com/files/149982/Webiness-Inventory-2.9-Shell-Upload.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-PFRQ-CMVX-39GF

Vulnerability from github – Published: 2023-01-18 00:30 – Updated: 2023-01-25 18:30
VLAI
Details

An unauthorized user could alter or write files with full control over the path and content of the file.

Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
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{
  "affected": [],
  "aliases": [
    "CVE-2022-46660"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-434"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2023-01-18T00:15:00Z",
    "severity": "MODERATE"
  },
  "details": "An unauthorized user could alter or write files with full control over the path and content of the file.",
  "id": "GHSA-pfrq-cmvx-39gf",
  "modified": "2023-01-25T18:30:49Z",
  "published": "2023-01-18T00:30:18Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2022-46660"
    },
    {
      "type": "WEB",
      "url": "https://digitalsupport.ge.com/s/article/GE-Digital-Product-Security-Advisory-GED-23-01"
    },
    {
      "type": "WEB",
      "url": "https://www.cisa.gov/uscert/ics/advisories/icsa-23-017-01"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N",
      "type": "CVSS_V3"
    }
  ]
}
Mitigation
Architecture and Design

Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.[REF-422] [REF-423]

Mitigation MIT-21
Architecture and Design

Strategy: Enforcement by Conversion

When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs.

Mitigation
Architecture and Design

Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically. [REF-423]

Mitigation MIT-5
Implementation

Strategy: Input Validation

  • Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
  • When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
  • Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
  • For example, limiting filenames to alphanumeric characters can help to restrict the introduction of unintended file extensions.
Mitigation
Architecture and Design

Define a very limited set of allowable extensions and only generate filenames that end in these extensions. Consider the possibility of XSS (CWE-79) before allowing .html or .htm file types.

Mitigation
Implementation

Strategy: Input Validation

Ensure that only one extension is used in the filename. Some web servers, including some versions of Apache, may process files based on inner extensions so that "filename.php.gif" is fed to the PHP interpreter.[REF-422] [REF-423]

Mitigation
Implementation

When running on a web server that supports case-insensitive filenames, perform case-insensitive evaluations of the extensions that are provided.

Mitigation MIT-15
Architecture and Design

For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

Mitigation
Implementation

Do not rely exclusively on sanity checks of file contents to ensure that the file is of the expected type and size. It may be possible for an attacker to hide code in some file segments that will still be executed by the server. For example, GIF images may contain a free-form comments field.

Mitigation
Implementation

Do not rely exclusively on the MIME content type or filename attribute when determining how to render a file. Validating the MIME content type and ensuring that it matches the extension is only a partial solution.

Mitigation MIT-17
Architecture and Design Operation

Strategy: Environment Hardening

Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.

Mitigation MIT-22
Architecture and Design Operation

Strategy: Sandbox or Jail

  • Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
  • OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
  • This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
  • Be careful to avoid CWE-243 and other weaknesses related to jails.
CAPEC-1: Accessing Functionality Not Properly Constrained by ACLs

In applications, particularly web applications, access to functionality is mitigated by an authorization framework. This framework maps Access Control Lists (ACLs) to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application, or can run queries for data that they otherwise not supposed to.

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