Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2021-32654— Attacker can obtain write access to any federated share/public link

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 Server 存在安全漏洞，该漏洞源于公共链接可以作为联邦文件共享添加。攻击者可利用该漏洞接收任何联邦文件共享的写读权限。

CVSS 8.1 · High EPSS 1.85% · P78
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2021-32654

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Attacker can obtain write access to any federated share/public link
Source: CVE Program / CVE List V5
Vulnerability Description
Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to receive write/read privileges on any Federated File Share. Since public links can be added as federated file share, this can also be exploited on any public link. Users can upgrade to patched versions (19.0.11, 20.0.10 or 21.0.2) or, as a workaround, disable federated file sharing.
Source: CVE Program / CVE List V5
CVSS Information
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Source: CVE Program / CVE List V5
Vulnerability Type
通过用户控制密钥绕过授权机制
Source: CVE Program / CVE List V5
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 Server 存在安全漏洞，该漏洞源于公共链接可以作为联邦文件共享添加。攻击者可利用该漏洞接收任何联邦文件共享的写读权限。
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 < 19.0.11 -

II. Public POCs for CVE-2021-32654

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2021-32654

请登录查看更多情报信息。

Vendor Advisories for CVE-2021-32654 (2)

Other References for CVE-2021-32654 (1)

Same Patch Batch · nextcloud · 2021-06-01 · 6 CVEs total

CVE-2021-32652 8.8 HIGH Missing permission check on email metadata retrieval
CVE-2021-32656 8.6 HIGH Trusted servers exchange can be triggered by attacker
CVE-2021-32657 4.3 MEDIUM Malicious user could break user administration page
CVE-2021-32655 3.5 LOW Files Drop public link can be added as federated share
CVE-2021-32653 2.7 LOW Default settings leak federated cloud ID to lookup server of all users

IV. Related Vulnerabilities

Same product: security-advisories
Same vendor: nextcloud
Same weakness: CWE-639

V. Comments for CVE-2021-32654

No comments yet

Leave a comment