CVE-2021-21357: Typo3/cms form Broken Access Control Vulnerability

HIGH
Advisory Identifier: GHSA-3vg7-jw9m-pc3f
CVSS 8.3
CWE-20 CWE-434 CWE-22
Published
Advisory Summary

CVE-2021-21357 is a HIGH (CVSS 8.3) broken access control vulnerability (CWE-20: Improper Input Validation) affecting Typo3/cms form libraries in the Packagist ecosystem. The issue involves broken access control in form framework. Remediation is available by upgrading affected packages to version 8.7.40, 9.5.25, 10.4.14, 11.1.1.

CVE-2021-21357 at a Glance

CVE Identifier CVE-2021-21357
GHSA Identifier GHSA-3vg7-jw9m-pc3f
Severity HIGH
CVSS v3.1 Base Score 8.3
CWE Classification CWE-20: Improper Input Validation
Affected Product Typo3/cms form
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 8.3

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H/E:H/RL:O/RC:C).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity High (I:H)
Availability High (A:H)

How to Fix CVE-2021-21357

To remediate this vulnerability, upgrade all affected Typo3/cms form dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

typo3/cms-form fixed: 8.7.40
Upgrade typo3/cms-form to 8.7.40
typo3/cms-form fixed: 9.5.25
Upgrade typo3/cms-form to 9.5.25
typo3/cms-form fixed: 10.4.14
Upgrade typo3/cms-form to 10.4.14
typo3/cms-form fixed: 11.1.1
Upgrade typo3/cms-form to 11.1.1
typo3/cms-core fixed: 10.4.14
Upgrade typo3/cms-core to 10.4.14
typo3/cms-core fixed: 11.1.1
Upgrade typo3/cms-core to 11.1.1
typo3/cms-core fixed: 9.5.25
Upgrade typo3/cms-core to 9.5.25
typo3/cms fixed: 10.4.14
Upgrade typo3/cms to 10.4.14
typo3/cms fixed: 11.1.1
Upgrade typo3/cms to 11.1.1
typo3/cms fixed: 9.5.25
Upgrade typo3/cms to 9.5.25
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release:

inspect dependencies for typo3/cms-form

How to Check if You Are Affected

To determine whether your application is affected by CVE-2021-21357, inspect your project dependencies for Typo3/cms form:

inspect dependencies for typo3/cms-form

Analyze the terminal output to locate any version of Typo3/cms form in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 8.7.40), your application is affected.

Note: Verify declared build manifests and deployed runtime container environments.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. In Typo3/cms form, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Problem Due to improper input validation, attackers can by-pass restrictions of predefined options and submit arbitrary data in the Form Designer backend module of the Form Framework. In the default configuration of the Form Framework this allows attackers to explicitly allow arbitrary mime-types for file uploads - however, default _fileDenyPattern_ successfully blocked files like _.htaccess_ or _malicious.php_. Besides that, attackers can persist those files in any writable directory of the corresponding TYPO3 installation. A valid backend user account with access to the form module is needed to exploit this vulnerability. ### Solution Update to TYPO3 versions 8.7.40, 9.5.25, 10.4.14, 11.1.1 that fix the problem described. ### Credits Thanks to Richie Lee who reported this issue and to TYPO3 contributor Ralf Zimmermann who fixed the issue. ### References * [TYPO3-CORE-SA-2021-003](https://typo3.org/security/advisory/typo3-core-sa-2021-003)

CVE-2021-21357 Affected Typo3/cms form Versions

10 component(s)
Fixed Versions:
8.7.409.5.2510.4.1411.1.1
Product / Package Ecosystem Affected Versions Fixed Version
typo3/cms-form
Packagist
≥ 8.0.0
< 8.7.40
8.7.40
typo3/cms-form
Packagist
≥ 9.0.0
< 9.5.25
9.5.25
typo3/cms-form
Packagist
≥ 10.0.0
< 10.4.14
10.4.14
typo3/cms-form
Packagist
≥ 11.0.0
< 11.1.1
11.1.1
typo3/cms-core
Packagist
≥ 10.0.0
< 10.4.14
10.4.14
typo3/cms-core
Packagist
≥ 11.0.0
< 11.1.1
11.1.1
typo3/cms-core
Packagist
≥ 9.0.0
< 9.5.25
9.5.25
typo3/cms
Packagist
≥ 10.0.0
< 10.4.14
10.4.14
typo3/cms
Packagist
≥ 11.0.0
< 11.1.1
11.1.1
typo3/cms
Packagist
≥ 9.0.0
< 9.5.25
9.5.25

References

Frequently Asked Questions

What is CVE-2021-21357?
CVE-2021-21357 is a security vulnerability in Typo3/cms form involving Broken Access Control in Form Framework under CWE-20: Improper Input Validation.
Which Typo3/cms form versions are affected?
Affected versions include releases prior to 8.7.40, 9.5.25, 10.4.14, 11.1.1 across affected packages: typo3/cms-form, typo3/cms-core, typo3/cms.
What version fixes CVE-2021-21357?
Upgrading to 8.7.40, 9.5.25, 10.4.14, 11.1.1 (or the latest patched release for your respective branch) resolves the vulnerability.
Is typo3/cms-form affected?
Yes, typo3/cms-form is affected in releases prior to 8.7.40, 9.5.25, 10.4.14, 11.1.1. Upgrade your dependency to 8.7.40, 9.5.25, 10.4.14, 11.1.1 or later.
Is typo3/cms-core affected?
Yes, typo3/cms-core is affected in releases prior to 10.4.14, 11.1.1, 9.5.25. Upgrade your dependency to 10.4.14, 11.1.1, 9.5.25 or later.
What is the CVSS score of CVE-2021-21357?
CVE-2021-21357 has a CVSS v3.1 base score of 8.3 (HIGH) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H/E:H/RL:O/RC:C.
What CWE is associated with CVE-2021-21357?
CVE-2021-21357 is classified under CWE-20: Improper Input Validation (The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.).
How can I check Packagist dependencies for CVE-2021-21357?
Run the dependency tree command: 'inspect dependencies for typo3/cms-form'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-3vg7-jw9m-pc3f",
  "modified" : "2021-03-29T18:01:00Z",
  "published" : "2021-03-23T01:53:57Z",
  "aliases" : [ "CVE-2021-21357" ],
  "summary" : "Broken Access Control in Form Framework",
  "details" : "\n### Problem\nDue to improper input validation, attackers can by-pass restrictions of predefined options and submit arbitrary data in the Form Designer backend module of the Form Framework.\n\nIn the default configuration of the Form Framework this allows attackers to explicitly allow arbitrary mime-types for file uploads - however, default _fileDenyPattern_ successfully blocked files like _.htaccess_ or _malicious.php_. Besides that, attackers can persist those files in any writable directory of the corresponding TYPO3 installation.\n\nA valid backend user account with access to the form module is needed to exploit this vulnerability.\n\n### Solution\nUpdate to TYPO3 versions 8.7.40, 9.5.25, 10.4.14, 11.1.1 that fix the problem described.\n\n### Credits\nThanks to Richie Lee who reported this issue and to TYPO3 contributor Ralf Zimmermann who fixed the issue.\n\n### References\n* [TYPO3-CORE-SA-2021-003](https://typo3.org/security/advisory/typo3-core-sa-2021-003)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:H/E:H/RL:O/RC:C"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-form"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "8.0.0"
      }, {
        "fixed" : "8.7.40"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 8.7.39"
    }
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-form"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.0.0"
      }, {
        "fixed" : "9.5.25"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 9.5.24"
    }
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-form"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.0.0"
      }, {
        "fixed" : "10.4.14"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 10.4.13"
    }
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-form"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0"
      }, {
        "fixed" : "11.1.1"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 11.1.0"
    }
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.0.0"
      }, {
        "fixed" : "10.4.14"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0"
      }, {
        "fixed" : "11.1.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms-core"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.0.0"
      }, {
        "fixed" : "9.5.25"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.0.0"
      }, {
        "fixed" : "10.4.14"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.0.0"
      }, {
        "fixed" : "11.1.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "typo3/cms"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "9.0.0"
      }, {
        "fixed" : "9.5.25"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-3vg7-jw9m-pc3f"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2021-21357"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms-core/CVE-2021-21357.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms/CVE-2021-21357.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://packagist.org/packages/typo3/cms-form"
  }, {
    "type" : "WEB",
    "url" : "https://typo3.org/security/advisory/typo3-core-sa-2021-003"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-20", "CWE-22", "CWE-434" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-03-23T01:41:49Z",
    "nvd_published_at" : "2021-03-23T02:15:00Z"
  }
}