CVE-2021-37630— Secret Circle can be joined without approval in Nextcloud Circles
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I. Basic Information for CVE-2021-37630
Vulnerability Information
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Vulnerability Title
Secret Circle can be joined without approval in Nextcloud Circles
Source: NVD (National Vulnerability Database)
Vulnerability Description
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.
Source: NVD (National Vulnerability Database)
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Source: NVD (National Vulnerability Database)
Vulnerability Type
通过用户控制密钥绕过授权机制
Source: NVD (National Vulnerability Database)
Vulnerability Title
Nextcloud 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Nextcloud是德国Nextcloud公司的一套开源的自托管文件同步和共享的通信应用平台。 Nextcloud Circles存在安全漏洞，该漏洞源于在受影响的版本中，Nextcloud Circles应用程序允许任何用户加入任何“秘密圈子”，而无需征得圈子所有者的同意，泄露私人信息。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)
Affected Products
| Vendor | Product | Affected Versions | CPE | Subscribe |
|---|---|---|---|---|
| nextcloud | security-advisories | < 0.19.15 | - |
II. Public POCs for CVE-2021-37630
| # | POC Description | Source Link | Shenlong Link |
|---|
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- https://hackerone.com/reports/1257624x_refsource_MISC
- https://github.com/nextcloud/circles/pull/768x_refsource_MISC
- https://nvd.nist.gov/vuln/detail/CVE-2021-37630
Same Patch Batch · nextcloud · 2021-09-07 · 9 CVEs total
| CVE-2021-32802 | 9.3 CRITICAL | Preview generation used third-party library not suited for user-generated content in Nextc |
| CVE-2021-32800 | 8.1 HIGH | Bypass of Two Factor Authentication in Nextcloud server |
| CVE-2021-37628 | 7.5 HIGH | File Drop can be bypassed using Richdocuments app in nextcloud |
| CVE-2021-37631 | 6.5 MEDIUM | Circle can be accessed by non-Circle members in Nextcloud Deck |
| CVE-2021-32782 | 5.8 MEDIUM | Cross-Site Scripting in Nextcloud Circles |
| CVE-2021-32801 | 5.5 MEDIUM | Exceptions may have logged Encryption-at-Rest key content in Nextcloud server |
| CVE-2021-32766 | 5.3 MEDIUM | Nextcloud Text app can disclose existence of folders in "File Drop" link share |
| CVE-2021-37629 | 5.3 MEDIUM | Lack of ratelimit on Richdocuments OCS endpoint in nextcloud |
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V. Comments for CVE-2021-37630
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