CVE-2021-32733

XSS in Nextcloud Text application

MEDIUM
6.1
CVSS Score
Published: July 12, 2021 at 09:05 PM UTC
Updated: June 17, 2026 at 03:53 AM UTC
1 product affected across 1 vendorNextcloud/server

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Severity
MEDIUM6.1
Exploit prediction
EPSS 1%

Description

Nextcloud Text is a collaborative document editing application that uses Markdown. A cross-site scripting vulnerability is present in versions prior to 19.0.13, 20.0.11, and 21.0.3. The Nextcloud Text application shipped with Nextcloud server used a `text/html` Content-Type when serving files to users. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, use a browser that has support for Content-Security-Policy.

Affected

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

v < 19.0.1320.0.0 ≤ v < 20.0.1121.0.0 ≤ v < 21.0.3
Affected range stops below 19.0.13, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.0.11, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.0.3, 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)

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
LOW
Integrity
LOW
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-79

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