CVE-2021-32689— Nextcloud Talk not properly disassociating users from chats after account deletion
Quick assessment
Affected
nextcloud security-advisories
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.
Nextcloud Talk是德国Nextcloud公司的一款自托管的本地音频/视频和聊天通信服务。 Nextcloud Talk 11.2.2之前版本存在安全漏洞，该漏洞源于如果用户能够重用以前使用过的用户名，他们就可以访问发送给之前使用该用户名的任何聊天消息。
Possible ATT&CK Techniques 1 AI
T1136.003 · Cloud Account
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I. Basic Information for CVE-2021-32689
Vulnerability Information
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Vulnerability Title
Nextcloud Talk not properly disassociating users from chats after account deletion
Source: CVE Program / CVE List V5
Vulnerability Description
Nextcloud Talk is a fully on-premises audio/video and chat communication service. In versions prior to 11.2.2, if a user was able to reuse an earlier used username, they could get access to any chat message sent to the previous user with this username. The issue was patched in versions 11.2.2 and 11.3.0. As a workaround, don't allow users to choose usernames themselves. This is the default behaviour of Nextcloud, but some user providers may allow doing so.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Source: CVE Program / CVE List V5
Vulnerability Type
不正确的属主授予
Source: CVE Program / CVE List V5
Vulnerability Title
Nextcloud Talk 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Nextcloud Talk是德国Nextcloud公司的一款自托管的本地音频/视频和聊天通信服务。 Nextcloud Talk 11.2.2之前版本存在安全漏洞，该漏洞源于如果用户能够重用以前使用过的用户名，他们就可以访问发送给之前使用该用户名的任何聊天消息。
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 | < 11.2.2 | - |
|
II. Public POCs for CVE-2021-32689
| # | POC Description | Source Link | Shenlong Link |
|---|
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Patches & Fixes for CVE-2021-32689 (1)
-
https://github.com/nextcloud/spreed/pull/5633 x_refsource_MISC
Vendor Advisories for CVE-2021-32689 (1)
Other References for CVE-2021-32689 (2)
-
https://github.com/nextcloud/spreed/releases/tag/v11.2.2 x_refsource_MISC
-
https://hackerone.com/reports/1200700 x_refsource_MISC
Same Patch Batch · nextcloud · 2021-07-12 · 14 CVEs total
| CVE-2021-32688 | 8.8 HIGH | Application specific tokens can change their own scope |
| CVE-2021-32726 | 7.1 HIGH | Webauthn tokens not removed after user has been deleted |
| CVE-2021-32727 | 5.7 MEDIUM | End-to-end encryption device setup did not verify public key |
| CVE-2021-32741 | 5.3 MEDIUM | Lack of ratelimit on public share link mount endpoint |
| CVE-2021-32705 | 5.3 MEDIUM | Lack of ratelimit on public DAV endpoint |
| CVE-2021-32703 | 5.3 MEDIUM | Lack of ratelimit on shareinfo endpoint |
| CVE-2021-32733 | 4.8 MEDIUM | XSS in Nextcloud Text application |
| CVE-2021-32707 | 4.3 MEDIUM | Bypass of image blocking in Nextcloud Mail |
| CVE-2021-32678 | 3.7 LOW | Ratelimit not applied on OCS API responses |
| CVE-2021-32725 | 3.5 LOW | Default share permissions not respected for federated reshares |
| CVE-2021-32679 | 3.5 LOW | Filenames not escaped by default in controllers using DownloadResponse |
| CVE-2021-32680 | 3.3 LOW | Audit log is not properly logging unsetting of share expiration date |
| CVE-2021-32734 | 3.1 LOW | File path disclosure of shared files in Nextcloud Text application |
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V. Comments for CVE-2021-32689
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