PT-2023-5256 · Nextcloud+2 · Nextcloud Server+2

Carl_Schwan · Published 2023-08-10 · Updated 2025-01-24 · CVE-2023-39952

Positive Technologies (AI Summary)

CVSS v2.0

6.8

Medium

Base vector

AV:N/AC:L/Au:S/C:C/I:N/A:N

Name of the Vulnerable Software and Affected Versions Nextcloud Server versions 22.0.0 through 22.2.10.12 Nextcloud Server versions 23.0.0 through 23.0.12.7 Nextcloud Server versions 24.0.0 through 24.0.12.3 Nextcloud Server versions 25.0.0 through 25.0.7 Nextcloud Server versions 26.0.0 through 26.0.2

Description The issue is related to incorrect access control in Nextcloud Server, allowing a user to access files inside a subfolder of a groupfolder accessible to them, even if advanced permissions would block access to the subfolder. This can enable a remote attacker to gain unauthorized access to protected information.

Recommendations For Nextcloud Server versions 22.0.0 through 22.2.10.12, update to version 22.2.10.13 or later. For Nextcloud Server versions 23.0.0 through 23.0.12.7, update to version 23.0.12.8 or later. For Nextcloud Server versions 24.0.0 through 24.0.12.3, update to version 24.0.12.4 or later. For Nextcloud Server versions 25.0.0 through 25.0.7, update to version 25.0.8 or later. For Nextcloud Server versions 26.0.0 through 26.0.2, update to version 26.0.3 or later.

Exploit

Fix

Improper Access Control

Weakness Enumeration

CWE-284

Related Identifiers

ALT-PU-2023-7785

ALT-PU-2025-1855

BDU:2023-05873

CVE-2023-39952

GHSA-CQ8W-V4FH-4RJQ

Affected Products

Alt Linux

Nextcloud Server

Red Os

References · 11

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/39xxx/CVE-2023-39952.json · Exploit
• https://github.com/nextcloud/server/pull/38890 · Patch
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-cq8w-v4fh-4rjq · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2023-39952 · Security Note
• https://bdu.fstec.ru/vul/2023-05873 · Security Note
• https://osv.dev/vulnerability/CVE-2023-39952 · Vendor Advisory
• https://github.com/nextcloud/groupfolders/issues/1906 · Note
• https://redos.red-soft.ru/support/secure · Note
• https://redos.red-soft.ru/support/secure/uyazvimosti/support/secure/uyazvimosti/mnozhestvennye-uyazvimosti-nextcloud-cve-2023-39958-cve-2023-39959-cve-2023-39962-cve-2023-39963-cve · Note
• https://t.me/cvenotify/56667 · Telegram Post
• https://hackerone.com/reports/1808079 · Note