CVE-2021-31611 Vulnerability Analysis & Exploit Details

CVE-2021-31611
Vulnerability Scoring

5.7
/10
Significant Risk

Security assessments indicate that CVE-2021-31611 presents a notable risk, potentially requiring prompt mitigation.

Attack Complexity Details

  • Attack Complexity: Low
    Exploits can be performed without significant complexity or special conditions.
  • Attack Vector: Adjacent_network
    Attack Vector Under Analysis
  • Privileges Required: None
    No privileges are required for exploitation.
  • Scope: Unchanged
    Exploit remains within the originally vulnerable component.
  • User Interaction: Required
    User interaction is necessary for successful exploitation.

CVE-2021-31611 Details

Status: Modified

Last updated: 🕕 21 Nov 2024, 06:06 UTC
Originally published on: 🕖 07 Sep 2021, 07:15 UTC

Time between publication and last update: 1170 days

CVSS Release: version 3

CVSS3 Source

nvd@nist.gov

CVSS3 Type

Primary

CVSS3 Vector

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

CVE-2021-31611 Vulnerability Summary

CVE-2021-31611: The Bluetooth Classic implementation on Zhuhai Jieli AC690X and AC692X devices does not properly handle an out-of-order LMP Setup procedure that is followed by a malformed LMP packet, allowing attackers in radio range to deadlock a device via a crafted LMP packet. The user needs to manually reboot the device to restore communication.

Assessing the Risk of CVE-2021-31611

Access Complexity Graph

The exploitability of CVE-2021-31611 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-2021-31611

With low attack complexity and no required privileges, CVE-2021-31611 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-2021-31611, 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-2021-31611, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.

  • Confidentiality: None
    CVE-2021-31611 has no significant impact on data confidentiality.
  • Integrity: None
    CVE-2021-31611 poses no threat to data integrity.
  • Availability: High
    CVE-2021-31611 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: 0.076% (probability of exploit)

EPSS Percentile: 36.03% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 63.97% of others.

CVE-2021-31611 References

External References

CWE Common Weakness Enumeration

CWE-667

CAPEC Common Attack Pattern Enumeration and Classification

  • Forced Deadlock CAPEC-25 The adversary triggers and exploits a deadlock condition in the target software to cause a denial of service. A deadlock can occur when two or more competing actions are waiting for each other to finish, and thus neither ever does. Deadlock conditions can be difficult to detect.
  • Leveraging Race Conditions CAPEC-26 The adversary targets a race condition occurring when multiple processes access and manipulate the same resource concurrently, and the outcome of the execution depends on the particular order in which the access takes place. The adversary can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance, a race condition can occur while accessing a file: the adversary can trick the system by replacing the original file with their version and cause the system to read the malicious file.
  • Leveraging Race Conditions via Symbolic Links CAPEC-27 This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to them. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file they will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary file.

Vulnerable Configurations

  • cpe:2.3:o:zh-jieli:ac6901_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:zh-jieli:ac6901_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:zh-jieli:ac6901:-:*:*:*:*:*:*:*
    cpe:2.3:h:zh-jieli:ac6901:-:*:*:*:*:*:*:*
  • cpe:2.3:o:zh-jieli:ac6925_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:zh-jieli:ac6925_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:zh-jieli:ac6925:-:*:*:*:*:*:*:*
    cpe:2.3:h:zh-jieli:ac6925:-:*:*:*:*:*:*:*
  • cpe:2.3:o:zh-jieli:ac6926_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:zh-jieli:ac6926_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:zh-jieli:ac6926:-:*:*:*:*:*:*:*
    cpe:2.3:h:zh-jieli:ac6926:-:*:*:*:*:*:*:*
  • cpe:2.3:o:zh-jieli:ac6928_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:zh-jieli:ac6928_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:zh-jieli:ac6928:-:*:*:*:*:*:*:*
    cpe:2.3:h:zh-jieli:ac6928:-:*:*:*:*:*:*:*
  • cpe:2.3:o:zh-jieli:ac6921_firmware:-:*:*:*:*:*:*:*
    cpe:2.3:o:zh-jieli:ac6921_firmware:-:*:*:*:*:*:*:*
  • cpe:2.3:h:zh-jieli:ac6921:-:*:*:*:*:*:*:*
    cpe:2.3:h:zh-jieli:ac6921:-:*:*:*:*:*:*:*

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