CVE-2021-37334

published 2021-08-25

CVE-2021-37334: Umbraco Forms version 4.0.0 up to and including 8.7.5 and below are vulnerable to a security flaw that could lead to a remote code execution attack and/or…

Priority P2 63 critical 9.8 CVSS 3.1

AV N AC L PR N UI N S U C H I H A H

Umbraco Forms version 4.0.0 up to and including 8.7.5 and below are vulnerable to a security flaw that could lead to a remote code execution attack and/or arbitrary file deletion. A vulnerability occurs because validation of the file extension is performed after the file has been stored in a temporary directory. By default, files are stored within the application directory structure at %BASEDIR%/APP_DATA/TEMP/FileUploads/. Whilst access to this directory is restricted by the root web.config file, it is possible to override this restriction by uploading another specially crafted web.config file to the temporary directory. It is possible to exploit this flaw to upload a malicious script file to execute arbitrary code and system commands on the server.

Affected

16 ranges

Vendor	Product	Version range	Fixed in
umbraco	forms	>= 4.0.0 < 4.4.9	4.4.9
umbraco	forms	>= 6.0.0 < 6.0.10	6.0.10
umbraco	forms	>= 7.0.0 < 7.0.7	7.0.7
umbraco	forms	>= 7.1.0 < 7.1.4	7.1.4
umbraco	forms	>= 7.2.0 < 7.2.1	7.2.1
umbraco	forms	>= 7.3.0 < 7.3.2	7.3.2
umbraco	forms	>= 7.4.0 < 7.4.3	7.4.3
umbraco	forms	>= 7.5.0 < 7.5.4	7.5.4
umbraco	forms	>= 8.0.0 < 8.0.2	8.0.2
umbraco	forms	>= 8.1.0 < 8.1.6	8.1.6
umbraco	forms	>= 8.2.0 < 8.2.3	8.2.3
umbraco	forms	>= 8.3.0 < 8.3.4	8.3.4
umbraco	forms	>= 8.4.0 < 8.4.4	8.4.4
umbraco	forms	>= 8.5.0 < 8.5.7	8.5.7
umbraco	forms	>= 8.6.0 < 8.6.2	8.6.2
umbraco	forms	>= 8.7.0 < 8.7.6	8.7.6

CVSS provenance

nvd v3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 9.3 CRITICAL AV:N/AC:M/Au:N/C:C/I:C/A:C

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