SB2017032810 - Multiple vulnerabilities in Nextcloud Server

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Cross-site scripting (CVE-ID: CVE-2016-9459)

The vulnerability allows a remote non-authenticated attacker to read and manipulate data.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are vulnerable to a log pollution vulnerability potentially leading to a local XSS. The download log functionality in the admin screen is delivering the log in JSON format to the end-user. The file was delivered with an attachment disposition forcing the browser to download the document. However, Firefox running on Microsoft Windows would offer the user to open the data in the browser as an HTML document. Thus any injected data in the log would be executed.

2) Improper access control (CVE-ID: CVE-2016-9461)

The vulnerability allows a remote authenticated user to manipulate data.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying edit check permissions on WebDAV copy actions. The WebDAV endpoint was not properly checking the permission on a WebDAV COPY action. This allowed an authenticated attacker with access to a read-only share to put new files in there. It was not possible to modify existing files.

3) Improper access control (CVE-ID: CVE-2016-9462)

The vulnerability allows a remote authenticated user to manipulate data.

Nextcloud Server before 9.0.52 & ownCloud Server before 9.0.4 are not properly verifying restore privileges when restoring a file. The restore capability of Nextcloud/ownCloud was not verifying whether a user has only read-only access to a share. Thus a user with read-only access was able to restore old versions.

Remediation

Install update from vendor's website.

References

• http://www.securityfocus.com/bid/97284
• https://github.com/nextcloud/server/commit/94975af6db1551c2d23136c2ea22866a5b416070
• https://github.com/owncloud/core/commit/044ee072a647636b1a17c89265c7233b35371335
• https://github.com/owncloud/core/commit/b7fa2c5dc945b40bc6ed0a9a0e47c282ebf043e1
• https://github.com/owncloud/core/commit/efa35d621dc7ff975468e636a5d1c153511296dc
• https://hackerone.com/reports/146278
• https://nextcloud.com/security/advisory/?id=nc-sa-2016-002
• https://owncloud.org/security/advisory?id=oc-sa-2016-012
• http://www.securityfocus.com/bid/97276
• https://github.com/nextcloud/server/commit/3491400261c1454a9a30d3ec96969573330120cc
• https://github.com/owncloud/core/commit/0622e635d97cb17c5e1363e370bb8268cc3d2547
• https://github.com/owncloud/core/commit/121a3304a0c37ccda0e1b63ddc528cba9121a36e
• https://github.com/owncloud/core/commit/acbbadb71ceee7f01da347f7dcd519beda78cc47
• https://github.com/owncloud/core/commit/c0a4b7b3f38ad2eaf506484b3b92ec678cb021c9
• https://hackerone.com/reports/145950
• https://nextcloud.com/security/advisory/?id=nc-sa-2016-004
• https://owncloud.org/security/advisory/?id=oc-sa-2016-014
• http://www.securityfocus.com/bid/97285
• https://github.com/nextcloud/server/commit/1208953ba1d4d55a18a639846bbcdd66a2d5bc5e
• https://github.com/owncloud/core/commit/23383080731d092e079986464a8c4c9ffcb79f4c
• https://github.com/owncloud/core/commit/3b056fa68ce502ceb0db9b446dab3b9e7b10dd13
• https://github.com/owncloud/core/commit/c93eca49c32428ece03dd67042772d5fa62c8d6e
• https://github.com/owncloud/core/commit/d31720b6f1e8c8dfeb5e8805ab35ad7c8000b2f1
• https://hackerone.com/reports/146067
• https://nextcloud.com/security/advisory/?id=nc-sa-2016-005
• https://owncloud.org/security/advisory/?id=oc-sa-2016-015