CVE-2021-32654

Attacker can obtain write access to any federated share/public link

CRITICAL
9.1
CVSS Score
Published: June 1, 2021 at 08:45 PM UTC
Updated: June 17, 2026 at 03:53 AM UTC
1 product affected across 1 vendorNextcloud/server

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Severity
CRITICAL9.1
Exploit prediction
EPSS 2%

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 19.0.1120.0.0 ≤ v < 20.0.1021.0.0 ≤ v < 21.0.2
Affected range stops below 19.0.11, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.0.10, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.0.2, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (3)

x_refsource_MISCPermissions RequiredThird Party Advisory
https://hackerone.com/reports/1170024
Vendor Advisoryx_refsource_GENTOOThird Party Advisory
https://security.gentoo.org/glsa/202208-17

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-639

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