CVE-2023-6827

Essential Real Estate <= 4.3.5 - Authenticated (Subscriber+) Arbitrary File Upload

2023-12-14 00:00
István Márton

Strategic Overview

Status
Patched in 4.4.0
Affected Plugin
Essential Real Estate
Affected Version
<= 4.3.5
CVSS
7.5High
Weakness type
CWE-434 · Unrestricted Upload of File with Dangerous Type
CVE
CVE-2023-6827
View all Essential Real Estate vulnerabilities

At a glance

CVE-2023-6827 is a high-severity Unrestricted Upload of File with Dangerous Type vulnerability in the Essential Real Estate WordPress plugin, affecting versions <= 4.3.5. It carries a CVSS score of 7.5 (reachable over the network; high confidentiality, integrity, availability impact). Exploitation requires an authenticated account at Subscriber level or above. The issue is fixed in version 4.4.0; sites on affected versions should update now. Disclosed December 2023, reported by István Márton.

Vulnerability Overview

The Essential Real Estate plugin for WordPress is vulnerable to arbitrary file uploads due to insufficient file type validation on the 'ajaxUploadFonts' function in versions up to, and including, 4.3.5. This makes it possible for authenticated attackers with subscriber-level capabilities or above, to upload arbitrary files on the affected site's server which may make remote code execution possible. CVE-2023-6140 appears to be a duplicate of this issue.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, and no interaction from a victim user. A successful exploit has high impact on confidentiality, integrity, availability — full site compromise territory.

CWE-434: Unrestricted Upload of File with Dangerous Type

Essential Real Estate <= 4.3.5 carries this weakness at ajaxUploadFonts, and reaching it takes an account at Subscriber level or above. An unrestricted file upload lets a caller store a file whose type or destination the application does not properly constrain.

If an uploaded file lands anywhere the server will execute, the flaw becomes remote code execution and the site should be treated as fully compromised. For Essential Real Estate the fix is 4.4.0: builds <= 4.3.5 are affected, anything from 4.4.0 onward is not.

Remediation

Update to version 4.4.0, or a newer patched version

How does WordSec protect against this?

An attacker needs Subscriber access first, so the firewall sees the attempt as traffic from a logged-in account: WordSec's web application firewall inspects request payloads before WordPress loads them. Classes like this one can leave something behind, so the staged malware scanner is the second half: it looks for dropped files and modified code rather than for the request that created them. None of that substitutes for the fix: Essential Real Estate 4.4.0 closes this, and updating the plugin is the step that ends it.

  • Firewall
  • Scanner
  • Alerts

External References

https://www.cve.org/CVERecord?id=CVE-2023-6827https://www.wordfence.com/threat-intel/vulnerabilities/id/8bb2ce22-077b-41dd-a2ff-cc1db9d20d38https://nvd.nist.gov/vuln/detail/CVE-2023-6827

Related records

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