CVE-2021-4356 Vulnerability Analysis & Exploit Details

CVE-2021-4356
Vulnerability Scoring

9.0
/10
Severe Risk

Cybersecurity professionals consider CVE-2021-4356 an immediate threat requiring urgent mitigation.

Attack Complexity Details

  • Attack Complexity: High
    Exploits require significant effort and special conditions.
  • Attack Vector: Network
    Vulnerability is exploitable over a network without physical access.
  • Privileges Required: None
    No privileges are required for exploitation.
  • Scope: Changed
    Successful exploitation can impact components beyond the vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2021-4356 Details

Status: Modified

Last updated: 🕡 21 Nov 2024, 06:37 UTC
Originally published on: 🕑 07 Jun 2023, 02:15 UTC

Time between publication and last update: 533 days

CVSS Release: version 3

CVSS3 Source

security@wordfence.com

CVSS3 Type

Secondary

CVSS3 Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H

CVE-2021-4356 Vulnerability Summary

CVE-2021-4356: The Frontend File Manager plugin for WordPress is vulnerable to Unauthenticated Arbitrary File Download in versions up to, and including, 18.2. This is due to lacking authentication protections, capability checks, and sanitization, all on the wpfm_file_meta_update AJAX action. This makes it possible for unauthenticated attackers to download arbitrary files on the site, potentially leading to site takeover.

Assessing the Risk of CVE-2021-4356

Access Complexity Graph

The exploitability of CVE-2021-4356 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).

Exploitability Analysis for CVE-2021-4356

CVE-2021-4356 presents a challenge to exploit due to its high attack complexity, but the absence of privilege requirements still makes it a viable target for skilled attackers. A thorough security review is advised.

Understanding AC and PR

A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.

Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.

Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.

CVSS Score Breakdown Chart

Above is the CVSS Sub-score Breakdown for CVE-2021-4356, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.

CIA Impact Analysis

Below is the Impact Analysis for CVE-2021-4356, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: High
    Exploiting CVE-2021-4356 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2021-4356 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2021-4356 can disrupt system operations, potentially causing complete denial of service (DoS).

Exploit Prediction Scoring System (EPSS)

The EPSS score estimates the probability that this vulnerability will be exploited in the near future.

EPSS Score: 0.52% (probability of exploit)

EPSS Percentile: 77.11% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 22.89% of others.

CVE-2021-4356 References

External References

CWE Common Weakness Enumeration

CWE-862

CAPEC Common Attack Pattern Enumeration and Classification

  • Exploitation of Thunderbolt Protection Flaws CAPEC-665 An adversary leverages a firmware weakness within the Thunderbolt protocol, on a computing device to manipulate Thunderbolt controller firmware in order to exploit vulnerabilities in the implementation of authorization and verification schemes within Thunderbolt protection mechanisms. Upon gaining physical access to a target device, the adversary conducts high-level firmware manipulation of the victim Thunderbolt controller SPI (Serial Peripheral Interface) flash, through the use of a SPI Programing device and an external Thunderbolt device, typically as the target device is booting up. If successful, this allows the adversary to modify memory, subvert authentication mechanisms, spoof identities and content, and extract data and memory from the target device. Currently 7 major vulnerabilities exist within Thunderbolt protocol with 9 attack vectors as noted in the Execution Flow.

Vulnerable Configurations

  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:-:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:-:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.3:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.3:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.4:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.4:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.5:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.5:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.6:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.6:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.7:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.7:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.8:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:1.8:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:2.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:2.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:2.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:2.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.3:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.3:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.4:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.4:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.5:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.5:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.6:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.6:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.7:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.7:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.8:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.8:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.9:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:3.9:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:4.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:4.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:4.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:4.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:5.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.3:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.3:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.4:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.4:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.5:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.5:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.6:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.6:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.7:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.7:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.8:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.8:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.9:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:13.9:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.3:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.3:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.4:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.4:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.5:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.5:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.6:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.6:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.7:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.7:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.8:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.8:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.9:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:14.9:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.2:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.3:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.3:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.4:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.4:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.5:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.5:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.6:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.6:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.7:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.7:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.8:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.8:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.9:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:15.9:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:16.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:16.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:17.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:17.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:17.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:17.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.0:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.0:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.1:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.1:*:*:*:*:wordpress:*:*
  • cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.2:*:*:*:*:wordpress:*:*
    cpe:2.3:a:najeebmedia:frontend_file_manager_plugin:18.2:*:*:*:*:wordpress:*:*

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