CVE-2020-26227: Typo3/cms core Cross-Site Scripting Vulnerability
MODERATECVE-2020-26227 is a MODERATE (CVSS 6.1) cross-site scripting vulnerability (CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) affecting Typo3/cms core libraries in the Packagist ecosystem. The issue involves cross-site scripting in fluid view helpers. Remediation is available by upgrading affected packages to version 9.5.23, 10.4.10, 8.7.38.
CVE-2020-26227 at a Glance
Security Impact
CVSS: 6.1
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N).
How to Fix CVE-2020-26227
To remediate this vulnerability, upgrade all affected Typo3/cms core dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade typo3/cms-core to 9.5.23
Upgrade typo3/cms-core to 10.4.10
Upgrade typo3/cms-core to 8.7.38
Upgrade typo3/cms to 10.4.10
Upgrade typo3/cms to 9.5.23
Upgrade typo3/cms to 8.7.38
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for typo3/cms-core
How to Check if You Are Affected
To determine whether your application is affected by CVE-2020-26227, inspect your project dependencies for Typo3/cms core:
inspect dependencies for typo3/cms-core
Analyze the terminal output to locate any version of Typo3/cms core in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 9.5.23), 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-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'), where the product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. In Typo3/cms core, 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
CVE-2020-26227 Affected Typo3/cms core Versions
6 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
typo3/cms-core
|
Packagist |
≥ 9.0.0
< 9.5.23
|
9.5.23
|
|
typo3/cms-core
|
Packagist |
≥ 10.0.0
< 10.4.10
|
10.4.10
|
|
typo3/cms-core
|
Packagist |
≥ 8.7.0
< 8.7.38
|
8.7.38
|
|
typo3/cms
|
Packagist |
≥ 10.0.0
< 10.4.10
|
10.4.10
|
|
typo3/cms
|
Packagist |
≥ 9.0.0
< 9.5.23
|
9.5.23
|
|
typo3/cms
|
Packagist |
≥ 8.7.0
< 8.7.38
|
8.7.38
|
References
Frequently Asked Questions
What is CVE-2020-26227?
Which Typo3/cms core versions are affected?
What version fixes CVE-2020-26227?
Is typo3/cms-core affected?
Is typo3/cms affected?
What is the CVSS score of CVE-2020-26227?
What CWE is associated with CVE-2020-26227?
How can I check Packagist dependencies for CVE-2020-26227?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-vqqx-jw6p-q3rf",
"modified" : "2021-01-07T22:34:28Z",
"published" : "2020-12-21T16:28:11Z",
"aliases" : [ "CVE-2020-26227" ],
"summary" : "Cross-Site Scripting in Fluid view helpers",
"details" : "> ### Meta\n> * CVSS: `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:F/RL:O/RC:C` (5.7)\n> * CWE-79\n\n### Problem\nIt has been discovered that system extension Fluid (`typo3/cms-fluid`) of the TYPO3 core is vulnerable to cross-site scripting passing user-controlled data as argument to Fluid view helpers.\n\n```\n<f:form ... fieldNamePrefix=\"{payload}\" />\n<f:be.labels.csh ... label=\"{payload}\" />\n<f:be.menus.actionMenu ... label=\"{payload}\" />\n```\n\n### Solution\nUpdate to TYPO3 versions 9.5.23 or 10.4.10 that fix the problem described.\n\n### Credits\nThanks to TYPO3 security team member Oliver Hader who reported this issue and to TYPO3 security team members Helmut Hummel & Oliver Hader who fixed the issue.\n\n### References\n* [TYPO3-CORE-SA-2020-010](https://typo3.org/security/advisory/typo3-core-sa-2020-010)",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms-core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.5.23"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms-core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "10.0.0"
}, {
"fixed" : "10.4.10"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms-core"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "8.7.0"
}, {
"fixed" : "8.7.38"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "10.0.0"
}, {
"fixed" : "10.4.10"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.0.0"
}, {
"fixed" : "9.5.23"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Packagist",
"name" : "typo3/cms"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "8.7.0"
}, {
"fixed" : "8.7.38"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/TYPO3/TYPO3.CMS/security/advisories/GHSA-vqqx-jw6p-q3rf"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-26227"
}, {
"type" : "WEB",
"url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms-core/CVE-2020-26227.yaml"
}, {
"type" : "WEB",
"url" : "https://github.com/FriendsOfPHP/security-advisories/blob/master/typo3/cms/CVE-2020-26227.yaml"
}, {
"type" : "WEB",
"url" : "https://packagist.org/packages/typo3/cms-core"
}, {
"type" : "WEB",
"url" : "https://typo3.org/security/advisory/typo3-core-sa-2020-010"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-79" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2020-12-21T16:11:44Z",
"nvd_published_at" : null
}
}