CVE-2021-32679
Nextcloud Server Malicious File Extension Trick
Description
Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.13, 20.0.11, and 21.0.3, filenames where not escaped by default in controllers using `DownloadResponse`. When a user-supplied filename was passed unsanitized into a `DownloadResponse`, this could be used to trick users into downloading malicious files with a benign file extension. This would show in UI behaviours where Nextcloud applications would display a benign file extension (e.g. JPEG), but the file will actually be downloaded with an executable file extension. The vulnerability is patched in versions 19.0.13, 20.0.11, and 21.0.3. Administrators of Nextcloud instances do not have a workaround available, but developers of Nextcloud apps may manually escape the file name before passing it into `DownloadResponse`.
INFO
Published Date :
July 12, 2021, 1:15 p.m.
Last Modified :
Nov. 7, 2023, 3:35 a.m.
Source :
[email protected]
Remotely Exploitable :
Yes !
Impact Score :
5.9
Exploitability Score :
2.8
Affected Products
The following products are affected by CVE-2021-32679
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.
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-2021-32679.
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-2021-32679 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2021-32679 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 [email protected]
May. 14, 2024
Action Type Old Value New Value -
CVE Modified by [email protected]
Nov. 07, 2023
Action Type Old Value New Value Added Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/ [No types assigned] Added Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/ [No types assigned] Removed Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/[email protected]/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/ Removed Reference GitHub, Inc. https://lists.fedoraproject.org/archives/list/[email protected]/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/ -
Modified Analysis by [email protected]
Oct. 26, 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 -
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] -
Modified Analysis by [email protected]
Sep. 20, 2021
Action Type Old Value New Value Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/ Mailing List, Third Party Advisory Changed Reference Type https://lists.fedoraproject.org/archives/list/[email protected]/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/ No Types Assigned https://lists.fedoraproject.org/archives/list/[email protected]/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/ Mailing List, Third Party Advisory Added CPE Configuration OR *cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* *cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:* -
CVE Modified by [email protected]
Jul. 22, 2021
Action Type Old Value New Value Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/J63NBVPR2AQCAWRNDOZSGRY5II4WS2CZ/ [No Types Assigned] Added Reference https://lists.fedoraproject.org/archives/list/[email protected]/message/BVZS26RDME2DYTKET5AECRIZDFUGR2AZ/ [No Types Assigned] -
Initial Analysis by [email protected]
Jul. 14, 2021
Action Type Old Value New Value Added CVSS V2 Metadata Victim must voluntarily interact with attack mechanism Added CVSS V2 NIST (AV:N/AC:M/Au:N/C:P/I:P/A:P) Added CVSS V3.1 NIST AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Changed Reference Type https://github.com/nextcloud/security-advisories/security/advisories/GHSA-3hjp-26x8-mhf6 No Types Assigned https://github.com/nextcloud/security-advisories/security/advisories/GHSA-3hjp-26x8-mhf6 Third Party Advisory Changed Reference Type https://github.com/nextcloud/server/pull/27354 No Types Assigned https://github.com/nextcloud/server/pull/27354 Patch, Third Party Advisory Changed Reference Type https://hackerone.com/reports/1215263 No Types Assigned https://hackerone.com/reports/1215263 Permissions Required Added CWE NIST CWE-116 Added CPE Configuration OR *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions up to (excluding) 19.0.13 *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions from (including) 20.0.0 up to (excluding) 20.0.11 *cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* versions from (including) 21.0.0 up to (excluding) 21.0.3
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2021-32679 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-2021-32679
weaknesses.
Exploit Prediction
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days.
0.36 }} 0.03%
score
0.71547
percentile