CVE-2021-37630 Vulnerability Analysis & Exploit Details

CVE-2021-37630
Vulnerability Scoring

6.5
/10
High Risk

If left unpatched, CVE-2021-37630 could lead to major system disruptions or data loss.

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-2021-37630 Details

Status: Modified

Last updated: 🕕 21 Nov 2024, 06:15 UTC
Originally published on: 🕗 07 Sep 2021, 20:15 UTC

Time between publication and last update: 1170 days

CVSS Release: version 3

CVSS3 Source

security-advisories@github.com

CVSS3 Type

Secondary

CVSS3 Vector

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

CVE-2021-37630 Vulnerability Summary

CVE-2021-37630: Nextcloud Circles is an open source social network built for the nextcloud ecosystem. In affected versions the Nextcloud Circles application allowed any user to join any "Secret Circle" without approval by the Circle owner leaking private information. It is recommended that Nextcloud Circles is upgraded to 0.19.15, 0.20.11 or 0.21.4. There are no workarounds for this issue.

Assessing the Risk of CVE-2021-37630

Access Complexity Graph

The exploitability of CVE-2021-37630 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-2021-37630

CVE-2021-37630 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-2021-37630, 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-2021-37630, 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-2021-37630 can result in unauthorized access to sensitive data, severely compromising data privacy.
  • Integrity: None
    CVE-2021-37630 poses no threat to data integrity.
  • Availability: None
    CVE-2021-37630 does not impact system availability.

Exploit Prediction Scoring System (EPSS)

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

EPSS Score: 0.1% (probability of exploit)

EPSS Percentile: 43.31% (lower percentile = lower relative risk)
This vulnerability is less risky than approximately 56.69% of others.

CVE-2021-37630 References

External References

CWE Common Weakness Enumeration

CWE-639

Vulnerable Configurations

  • cpe:2.3:a:nextcloud:circles:-:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:-:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.9.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.9.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.9.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.9.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.9.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.9.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.9.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.9.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.10.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.10.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.11.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.11.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.12.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.12.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.12.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.12.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.12.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.12.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.12.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.12.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.12.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.12.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.13.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.13.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.14.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.14.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.14.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.14.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.14.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.14.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.14.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.14.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.14.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.14.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.15.7:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.15.7:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.7:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.7:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.8:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.8:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.9:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.9:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.10:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.10:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.11:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.11:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.12:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.12:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.16.13:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.16.13:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.7:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.7:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.8:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.8:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.9:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.9:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.10:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.10:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.11:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.11:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.12:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.12:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.13:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.13:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.17.14:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.17.14:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.7:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.7:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.8:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.8:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.9:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.9:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.10:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.10:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.11:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.11:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.12:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.12:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.18.13:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.18.13:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.19.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.19.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.19.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.19.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.19.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.19.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.19.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.19.3:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.19.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.19.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.4:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.4:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.5:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.5:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.6:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.6:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.7:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.7:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.8:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.8:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.9:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.9:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.20.10:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.20.10:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.21.0:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.21.0:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.21.1:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.21.1:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.21.2:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.21.2:*:*:*:*:*:*:*
  • cpe:2.3:a:nextcloud:circles:0.21.3:*:*:*:*:*:*:*
    cpe:2.3:a:nextcloud:circles:0.21.3:*:*:*:*:*:*:*

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