PT-2017-10155 · Nextcloud · Nextcloud Server

Dalt4Sec · Published 2017-03-28 · Updated 2019-10-09 · CVE-2016-9464

Positive Technologies (AI Summary)

CVSS v3.1

4.3

Medium

Base vector

AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N

Name of the Vulnerable Software and Affected Versions Nextcloud Server versions prior to 9.0.54 Nextcloud Server version 10.0.0

Description The issue arises from an improper authorization check on removing shares. Specifically, the Sharing Backend in Nextcloud differentiates between shares to users and groups. In the case of a received group share, users should be able to unshare the file to themselves but not to the whole group. However, the previous API implementation simply unshared the file to all users in the group.

Recommendations For Nextcloud Server versions prior to 9.0.54, update to version 9.0.54 or later to resolve the issue. For Nextcloud Server version 10.0.0, update to a version later than 10.0.0 to resolve the issue.

Exploit

Fix

Improper Authorization

Weakness Enumeration

CWE-285

Related Identifiers

CVE-2016-9464

Affected Products

Nextcloud Server

References · 10

• 🔥 https://hackerone.com/reports/153905 · Exploit
• https://github.com/nextcloud/server/commit/a5471b4a3e3f30e99e4de39c97c0c3b3c2f1618f · Patch
• https://github.com/nextcloud/server/commit/e2c4f4f9aa11bc92e8f2212cce73841b922187e8 · Patch
• https://github.com/nextcloud/server/commit/3387e5d00fcf6b2ea6b285a091e5743f545e7202 · Patch
• https://github.com/nextcloud/server/commit/7289cb5ec0b812992ab0dfb889744b94bc0994f0 · Patch
• https://nextcloud.com/security/advisory/?id=nc-sa-2016-007 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2016-9464 · Security Note
• https://osv.dev/vulnerability/CVE-2016-9464 · Vendor Advisory
• https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-9464 · Note
• http://securityfocus.com/bid/97287 · Note