6.1

CVE-2021-32733: nextcloud nextcloud_server Cross-site Scripting

CVSS: 6.1v3.1MediumModified
Published 12-07-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-32733 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in nextcloud nextcloud_server. EPSS estimates a 1.11% chance of exploitation in the next 30 days, higher than 65.2% of scored vulnerabilities.

Overall risk
25/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.1/10
010
Medium · v3.1 (NVD)
EPSS score
1.11%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 12-07-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

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.

CVSS metrics

3 scores · 2 sources · 2 versions

EPSS trend

Probability

1.11%

Chance of exploitation in the next 30 days

Percentile

65%

Versus all other CVEs

30-day change

0.00 pp

From 1.11% on 19-09-2026

19-09-202619-10-2026
EPSS score
1.11%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Nextcloud2 products

1 vendor · 2 products

References

3 links