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10.0
HIGH CVSS 2.0
CVE-2021-32802
Nextcloud Image Preview Vulnerability
Description

Nextcloud server is an open source, self hosted personal cloud. Nextcloud supports rendering image previews for user provided file content. For some image types, the Nextcloud server was invoking a third-party library that wasn't suited for untrusted user-supplied content. There are several security concerns with passing user-generated content to this library, such as Server-Side-Request-Forgery, file disclosure or potentially executing code on the system. The risk depends on your system configuration and the installed library version. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. These versions do not use this library anymore. As a workaround users may disable previews by setting `enable_previews` to `false` in `config.php`.

INFO

Published Date :

Sept. 7, 2021, 10:15 p.m.

Last Modified :

Nov. 21, 2024, 6:07 a.m.

Remotely Exploit :

Yes !

Source :

[email protected]
Affected Products

The following products are affected by CVE-2021-32802 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Nextcloud nextcloud_server
2 Nextcloud notes
: Total Affected Vendor : 1 | Products : 2
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 2.0 HIGH [email protected]
CVSS 3.1 CRITICAL [email protected]
CVSS 3.1 CRITICAL [email protected]
Solution
Upgrade Nextcloud Server to address an image preview vulnerability.
  • Upgrade Nextcloud Server to version 20.0.12, 21.0.4, 22.1.0 or later.
  • Update the affected packages.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2021-32802.

URL Resource
https://docs.nextcloud.com/server/21/admin_manual/configuration_files/previews_configuration.html#disabling-previews Vendor Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7 Mitigation Third Party Advisory
https://hackerone.com/reports/1261413 Permissions Required Third Party Advisory
https://security.gentoo.org/glsa/202208-17 Third Party Advisory
https://docs.nextcloud.com/server/21/admin_manual/configuration_files/previews_configuration.html#disabling-previews Vendor Advisory
https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7 Mitigation Third Party Advisory
https://hackerone.com/reports/1261413 Permissions Required Third Party Advisory
https://security.gentoo.org/glsa/202208-17 Third Party Advisory
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2021-32802 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2021-32802 weaknesses.

CAPEC-175: Code Inclusion Code Inclusion CAPEC-201: Serialized Data External Linking Serialized Data External Linking CAPEC-228: DTD Injection DTD Injection CAPEC-251: Local Code Inclusion Local Code Inclusion CAPEC-252: PHP Local File Inclusion PHP Local File Inclusion CAPEC-253: Remote Code Inclusion Remote Code Inclusion CAPEC-263: Force Use of Corrupted Files Force Use of Corrupted Files CAPEC-538: Open-Source Library Manipulation Open-Source Library Manipulation CAPEC-549: Local Execution of Code Local Execution of Code CAPEC-640: Inclusion of Code in Existing Process Inclusion of Code in Existing Process CAPEC-660: Root/Jailbreak Detection Evasion via Hooking Root/Jailbreak Detection Evasion via Hooking CAPEC-695: Repo Jacking Repo Jacking CAPEC-698: Install Malicious Extension Install Malicious Extension

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2021-32802 vulnerability anywhere in the article.

Results are limited to the first 20 news articles due to potential performance issues.

The following table lists the changes that have been made to the CVE-2021-32802 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by af854a3a-2127-422b-91ae-364da2661108

    Nov. 21, 2024

    Action Type Old Value New Value
    Added Reference https://docs.nextcloud.com/server/21/admin_manual/configuration_files/previews_configuration.html#disabling-previews
    Added Reference https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7
    Added Reference https://hackerone.com/reports/1261413
    Added Reference https://security.gentoo.org/glsa/202208-17
  • CVE Modified by [email protected]

    May. 14, 2024

    Action Type Old Value New Value
  • Modified Analysis by [email protected]

    Sep. 27, 2022

    Action Type Old Value New Value
    Changed Reference Type https://security.gentoo.org/glsa/202208-17 No Types Assigned https://security.gentoo.org/glsa/202208-17 Third Party Advisory
    Changed CPE Configuration OR *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions up to (excluding) 20.0.12 *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions from (including) 21.0.0 up to (excluding) 21.0.4 *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions from (including) 22.0.0 up to (excluding) 22.1.0 OR *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions up to (excluding) 20.0.12 *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions from (including) 21.0.0 up to (excluding) 21.0.4 *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions from (including) 22.0.0 up to (excluding) 22.1.0
  • CVE Modified by [email protected]

    Aug. 11, 2022

    Action Type Old Value New Value
    Added Reference https://security.gentoo.org/glsa/202208-17 [No Types Assigned]
  • Initial Analysis by [email protected]

    Sep. 14, 2021

    Action Type Old Value New Value
    Added CVSS V2 NIST (AV:N/AC:L/Au:N/C:C/I:C/A:C)
    Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    Changed Reference Type https://docs.nextcloud.com/server/21/admin_manual/configuration_files/previews_configuration.html#disabling-previews No Types Assigned https://docs.nextcloud.com/server/21/admin_manual/configuration_files/previews_configuration.html#disabling-previews Vendor Advisory
    Changed Reference Type https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7 No Types Assigned https://github.com/nextcloud/security-advisories/security/advisories/GHSA-m682-v4g9-wrq7 Mitigation, Third Party Advisory
    Changed Reference Type https://hackerone.com/reports/1261413 No Types Assigned https://hackerone.com/reports/1261413 Permissions Required, Third Party Advisory
    Added CWE NIST CWE-829
    Added CPE Configuration OR *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions up to (excluding) 20.0.12 *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions from (including) 21.0.0 up to (excluding) 21.0.4 *cpe:2.3:a:nextcloud:nextcloud:*:*:*:*:*:*:*:* versions from (including) 22.0.0 up to (excluding) 22.1.0
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.
Vulnerability Scoring Details
Base CVSS Score: 9.8
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality Impact
Integrity Impact
Availability Impact
Base CVSS Score: 10
Access Vector
Access Complexity
Authentication
Confidentiality Impact
Integrity Impact
Availability Impact
Exploit Prediction

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.

2.25 }} 0.46%

score

0.83929

percentile