CVE-2018-18942: Baserproject/basercms Remote Code Execution Vulnerability

HIGH
Advisory Identifier: GHSA-rjc2-x53r-6c9r
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CVSS 7.2
CWE-434
Published
Advisory Summary

CVE-2018-18942 is a HIGH (CVSS 7.2) remote code execution vulnerability (CWE-434: Unrestricted Upload of File with Dangerous Type) affecting Baserproject/basercms libraries in the Packagist ecosystem. The issue involves rce in basercms before 4.1.4. Remediation is available by upgrading affected packages to version 4.1.4.

CVE-2018-18942 at a Glance

CVE Identifier CVE-2018-18942
GHSA Identifier GHSA-rjc2-x53r-6c9r
Severity HIGH
CVSS v3.1 Base Score 7.2
CWE Classification CWE-434: Unrestricted Upload of File with Dangerous Type
Affected Product Baserproject/basercms
Package Ecosystem Packagist
Published Date
Last Updated

Security Impact

CVSS: 7.2

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H).

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

How to Fix CVE-2018-18942

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

baserproject/basercms fixed: 4.1.4 
Upgrade baserproject/basercms to 4.1.4
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 baserproject/basercms

How to Check if You Are Affected

To determine whether your application is affected by CVE-2018-18942, inspect your project dependencies for Baserproject/basercms:

inspect dependencies for baserproject/basercms

Analyze the terminal output to locate any version of Baserproject/basercms in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.1.4), 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-434: Unrestricted Upload of File with Dangerous Type, where the product allows the upload or transfer of dangerous file types that are automatically processed within its environment. In Baserproject/basercms, 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

In baserCMS before 4.1.4, `lib\Baser\Model\ThemeConfig.php` allows remote attackers to execute arbitrary PHP code via the `admin/theme_configs/form data[ThemeConfig][logo]` parameter.

CVE-2018-18942 Affected Baserproject/basercms Versions

1 component(s)
Fixed Versions:
4.1.4
Product / Package Ecosystem Affected Versions Fixed Version
baserproject/basercms
 Packagist
< 4.1.4
4.1.4

References

NVD — CVE-2018-18942 NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-18942
Baserproject/basercms Source Repository REPOSITORY
https://github.com/baserproject/basercms/issues/959
web.archive.org/web/20200130073341/... WEB
https://web.archive.org/web/20200130073341/https://basercms.net/release/4_1_4
web.archive.org/web/20211209034642/... WEB
https://web.archive.org/web/20211209034642/http://sunu11.com/2018/10/31/baserCMS

Frequently Asked Questions

What is CVE-2018-18942?
CVE-2018-18942 is a security vulnerability in Baserproject/basercms involving RCE in baserCMS before 4.1.4 under CWE-434: Unrestricted Upload of File with Dangerous Type.
Which Baserproject/basercms versions are affected?
Affected versions include releases prior to 4.1.4 across affected packages: baserproject/basercms.
What version fixes CVE-2018-18942?
Upgrading to 4.1.4 (or the latest patched release for your respective branch) resolves the vulnerability.
Is baserproject/basercms affected?
Yes, baserproject/basercms is affected in releases prior to 4.1.4. Upgrade your dependency to 4.1.4 or later.
What is the CVSS score of CVE-2018-18942?
CVE-2018-18942 has a CVSS v3.1 base score of 7.2 (HIGH) with vector string CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H.
What CWE is associated with CVE-2018-18942?
CVE-2018-18942 is classified under CWE-434: Unrestricted Upload of File with Dangerous Type (The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.).
How can I check Packagist dependencies for CVE-2018-18942?
Run the dependency tree command: 'inspect dependencies for baserproject/basercms'. 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
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-rjc2-x53r-6c9r",
  "modified" : "2023-07-07T18:19:54Z",
  "published" : "2022-05-13T01:19:42Z",
  "aliases" : [ "CVE-2018-18942" ],
  "summary" : "RCE in baserCMS before 4.1.4",
  "details" : "In baserCMS before 4.1.4, `lib\\Baser\\Model\\ThemeConfig.php` allows remote attackers to execute arbitrary PHP code via the `admin/theme_configs/form data[ThemeConfig][logo]` parameter.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Packagist",
      "name" : "baserproject/basercms"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.1.4"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2018-18942"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/baserproject/basercms/issues/959"
  }, {
    "type" : "WEB",
    "url" : "https://web.archive.org/web/20200130073341/https://basercms.net/release/4_1_4"
  }, {
    "type" : "WEB",
    "url" : "https://web.archive.org/web/20211209034642/http://sunu11.com/2018/10/31/baserCMS"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-434" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2023-07-07T18:19:54Z",
    "nvd_published_at" : "2018-11-05T09:29:00Z"
  }
}