CVE-2021-22737 Vulnerability Analysis & Exploit Details

CVE-2021-22737
Vulnerability Scoring

9.8
/10
Critical Risk

As a catastrophic security flaw, CVE-2021-22737 has severe implications, demanding immediate intervention.

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: None
    No privileges are required for exploitation.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: None
    No user interaction is necessary for exploitation.

CVE-2021-22737 Details

Status: Modified

Last updated: 🕠 21 Nov 2024, 05:50 UTC
Originally published on: 🕗 26 May 2021, 20:15 UTC

Time between publication and last update: 1274 days

CVSS Release: version 3

CVSS3 Source

nvd@nist.gov

CVSS3 Type

Primary

CVSS3 Vector

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

CVE-2021-22737 Vulnerability Summary

CVE-2021-22737: Insufficiently Protected Credentials vulnerability exists in homeLYnk (Wiser For KNX) and spaceLYnk V2.60 and prior that could cause unauthorized access of when credentials are discovered after a brute force attack.

Assessing the Risk of CVE-2021-22737

Access Complexity Graph

The exploitability of CVE-2021-22737 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-2021-22737

With low attack complexity and no required privileges, CVE-2021-22737 is an easy target for cybercriminals. Organizations should prioritize immediate mitigation measures to prevent unauthorized access and data breaches.

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-2021-22737, 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-2021-22737, 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-2021-22737 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2021-22737 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2021-22737 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: 0.222% (probability of exploit)

EPSS Percentile: 60.85% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 39.15% of others.

CVE-2021-22737 References

External References

CWE Common Weakness Enumeration

CWE-307

CAPEC Common Attack Pattern Enumeration and Classification

  • Dictionary-based Password Attack CAPEC-16 An attacker tries each of the words in a dictionary as passwords to gain access to the system via some user's account. If the password chosen by the user was a word within the dictionary, this attack will be successful (in the absence of other mitigations). This is a specific instance of the password brute forcing attack pattern. Dictionary Attacks differ from similar attacks such as Password Spraying (CAPEC-565) and Credential Stuffing (CAPEC-600), since they leverage unknown username/password combinations and don't care about inducing account lockouts.
  • Password Brute Forcing CAPEC-49 An adversary tries every possible value for a password until they succeed. A brute force attack, if feasible computationally, will always be successful because it will essentially go through all possible passwords given the alphabet used (lower case letters, upper case letters, numbers, symbols, etc.) and the maximum length of the password.
  • Use of Known Domain Credentials CAPEC-560 An adversary guesses or obtains (i.e. steals or purchases) legitimate credentials (e.g. userID/password) to achieve authentication and to perform authorized actions under the guise of an authenticated user or service.
  • Password Spraying CAPEC-565 In a Password Spraying attack, an adversary tries a small list (e.g. 3-5) of common or expected passwords, often matching the target's complexity policy, against a known list of user accounts to gain valid credentials. The adversary tries a particular password for each user account, before moving onto the next password in the list. This approach assists the adversary in remaining undetected by avoiding rapid or frequent account lockouts. The adversary may then reattempt the process with additional passwords, once enough time has passed to prevent inducing a lockout.
  • Credential Stuffing CAPEC-600 An adversary tries known username/password combinations against different systems, applications, or services to gain additional authenticated access. Credential Stuffing attacks rely upon the fact that many users leverage the same username/password combination for multiple systems, applications, and services.
  • Use of Known Kerberos Credentials CAPEC-652 An adversary obtains (i.e. steals or purchases) legitimate Kerberos credentials (e.g. Kerberos service account userID/password or Kerberos Tickets) with the goal of achieving authenticated access to additional systems, applications, or services within the domain.
  • Use of Known Operating System Credentials CAPEC-653 An adversary guesses or obtains (i.e. steals or purchases) legitimate operating system credentials (e.g. userID/password) to achieve authentication and to perform authorized actions on the system, under the guise of an authenticated user or service. This applies to any Operating System.

Vulnerable Configurations

  • cpe:2.3:o:schneider-electric:spacelynk_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:1.0.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:1.0.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:1.1.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:1.1.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:1.1.1:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:1.1.1:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:1.2.1:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:1.2.1:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.0.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.0.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.0.1:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.0.1:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.1.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.1.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.1.1:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.1.1:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.3.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.3.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.4.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.4.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.5.0:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.5.0:*:*:*:*:*:*:*
  • cpe:2.3:o:schneider-electric:spacelynk_firmware:2.5.1:*:*:*:*:*:*:*
    cpe:2.3:o:schneider-electric:spacelynk_firmware:2.5.1:*:*:*:*:*:*:*
  • cpe:2.3:h:schneider-electric:spacelynk:-:*:*:*:*:*:*:*
    cpe:2.3:h:schneider-electric:spacelynk:-:*:*:*:*:*:*:*
  • cpe:2.3:h:schneider-electric:homelynk:-:*:*:*:*:*:*:*
    cpe:2.3:h:schneider-electric:homelynk:-:*:*:*:*:*:*:*

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