CVE-2021-40866 Vulnerability Analysis & Exploit Details

CVE-2021-40866
Vulnerability Scoring

9.8
/10
Critical Risk

As a catastrophic security flaw, CVE-2021-40866 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-2021-40866 Details

Status: Modified

Last updated: 🕕 21 Nov 2024, 06:24 UTC
Originally published on: 🕗 13 Sep 2021, 08:15 UTC

Time between publication and last update: 1164 days

CVSS Release: version 3

CVSS3 Source

cve@mitre.org

CVSS3 Type

Secondary

CVSS3 Vector

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

CVE-2021-40866 Vulnerability Summary

CVE-2021-40866: Certain NETGEAR smart switches are affected by a remote admin password change by an unauthenticated attacker via the (disabled by default) /sqfs/bin/sccd daemon, which fails to check authentication when the authentication TLV is missing from a received NSDP packet. This affects GC108P before 1.0.8.2, GC108PP before 1.0.8.2, GS108Tv3 before 7.0.7.2, GS110TPP before 7.0.7.2, GS110TPv3 before 7.0.7.2, GS110TUP before 1.0.5.3, GS308T before 1.0.3.2, GS310TP before 1.0.3.2, GS710TUP before 1.0.5.3, GS716TP before 1.0.4.2, GS716TPP before 1.0.4.2, GS724TPP before 2.0.6.3, GS724TPv2 before 2.0.6.3, GS728TPPv2 before 6.0.8.2, GS728TPv2 before 6.0.8.2, GS750E before 1.0.1.10, GS752TPP before 6.0.8.2, GS752TPv2 before 6.0.8.2, MS510TXM before 1.0.4.2, and MS510TXUP before 1.0.4.2.

Assessing the Risk of CVE-2021-40866

Access Complexity Graph

The exploitability of CVE-2021-40866 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-2021-40866

With low attack complexity and no required privileges, CVE-2021-40866 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-2021-40866, 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-2021-40866, 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-2021-40866 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: High
    CVE-2021-40866 could allow unauthorized modifications to data, potentially affecting system reliability and trust.
  • Availability: High
    CVE-2021-40866 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: 0.169% (probability of exploit)

EPSS Percentile: 55.08% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 44.92% of others.

CVE-2021-40866 References

External References

CWE Common Weakness Enumeration

NVD-CWE-Other

Vulnerable Configurations

  • cpe:2.3:h:netgear:gc108p:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gc108p:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gc108pp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gc108pp:-:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs108t_firmware:5.4.2.29:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs108t_firmware:5.4.2.29:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs108tv3:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs108tv3:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs110tpp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs110tpp:-:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs110tp_firmware:5.4.2.29:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs110tp_firmware:5.4.2.29:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs110tp:v3:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs110tp:v3:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs110tup:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs110tup:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs308t:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs308t:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs310tp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs310tp:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs710tup:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs710tup:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs716tp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs716tp:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs716tpp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs716tpp:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs724tpp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs724tpp:-:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs724tp_firmware:1.1.1.29:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs724tp_firmware:1.1.1.29:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs724tp:v2:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs724tp:v2:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs728tpp_firmware:6.0.0.48:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs728tpp_firmware:6.0.0.48:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs728tpp:v2:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs728tpp:v2:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs728tp_firmware:6.0.0.48:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs728tp_firmware:6.0.0.48:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs728tp:v2:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs728tp:v2:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs750e_firmware:1.0.1.4:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs750e_firmware:1.0.1.4:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs750e:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs750e:-:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs752tpp_firmware:6.0.0.48:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs752tpp_firmware:6.0.0.48:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs752tpp:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs752tpp:-:*:*:*:*:*:*:*
  • cpe:2.3:o:netgear:gs752tp_firmware:6.0.0.48:*:*:*:*:*:*:*
    cpe:2.3:o:netgear:gs752tp_firmware:6.0.0.48:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:gs752tp:v2:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:gs752tp:v2:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:ms510txm:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:ms510txm:-:*:*:*:*:*:*:*
  • cpe:2.3:h:netgear:ms510txup:-:*:*:*:*:*:*:*
    cpe:2.3:h:netgear:ms510txup:-:*:*:*:*:*:*:*

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