CVE-2020-5756 Vulnerability Analysis & Exploit Details

CVE-2020-5756
Vulnerability Scoring

8.8
/10
Severe Risk

Cybersecurity professionals consider CVE-2020-5756 an immediate threat requiring urgent mitigation.

Attack Complexity Details

  • Attack Complexity: Low
    Exploits can be performed without significant complexity or special conditions.
  • Attack Vector: Network
    Vulnerability is exploitable over a network without physical access.
  • Privileges Required: Low
    Some privileges are necessary to exploit the vulnerability.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2020-5756 Details

Status: Analyzed

Last updated: 🕣 22 Jul 2020, 20:43 UTC
Originally published on: 🕘 17 Jul 2020, 21:15 UTC

Time between publication and last update: 4 days

CVSS Release: version 3

CVSS3 Source

nvd@nist.gov

CVSS3 Type

Primary

CVSS3 Vector

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

CVE-2020-5756 Vulnerability Summary

CVE-2020-5756: Grandstream GWN7000 firmware version 1.0.9.4 and below allows authenticated remote users to modify the system's crontab via undocumented API. An attacker can use this functionality to execute arbitrary OS commands on the router.

Assessing the Risk of CVE-2020-5756

Access Complexity Graph

The exploitability of CVE-2020-5756 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-2020-5756

CVE-2020-5756 presents an accessible attack vector with minimal effort required. Restricting access controls and implementing security updates are critical to reducing exploitation risks.

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-2020-5756, 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-2020-5756, 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-2020-5756 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2020-5756 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2020-5756 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: 1.349% (probability of exploit)

EPSS Percentile: 86.25% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 13.75% of others.

CVE-2020-5756 References

External References

CWE Common Weakness Enumeration

CWE-489

CAPEC Common Attack Pattern Enumeration and Classification

  • Exploit Non-Production Interfaces CAPEC-121 An adversary exploits a sample, demonstration, test, or debug interface that is unintentionally enabled on a production system, with the goal of gleaning information or leveraging functionality that would otherwise be unavailable.
  • Root/Jailbreak Detection Evasion via Debugging CAPEC-661 An adversary inserts a debugger into the program entry point of a mobile application to modify the application binary, with the goal of evading Root/Jailbreak detection. Mobile device users often Root/Jailbreak their devices in order to gain administrative control over the mobile operating system and/or to install third-party mobile applications that are not provided by authorized application stores (e.g. Google Play Store and Apple App Store). Rooting/Jailbreaking a mobile device also provides users with access to system debuggers and disassemblers, which can be leveraged to exploit applications by dumping the application's memory at runtime in order to remove or bypass signature verification methods. This further allows the adversary to evade Root/Jailbreak detection mechanisms, which can result in execution of administrative commands, obtaining confidential data, impersonating legitimate users of the application, and more.

Vulnerable Configurations

  • cpe:2.3:o:grandstream:gwn7000_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:grandstream:gwn7000_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:o:grandstream:gwn7000_firmware:1.0.6.32:*:*:*:*:*:*:*
    cpe:2.3:o:grandstream:gwn7000_firmware:1.0.6.32:*:*:*:*:*:*:*
  • cpe:2.3:h:grandstream:gwn7000:-:*:*:*:*:*:*:*
    cpe:2.3:h:grandstream:gwn7000:-:*:*:*:*:*:*:*

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