PT-2023-5259 · Nextcloud+2 · Nextcloud Server+2

Themarkib · Published 2023-08-10 · Updated 2025-01-24 · CVE-2023-39959

Positive Technologies (AI Summary)

CVSS v2.0

5.0

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions Nextcloud Server versions 25.0.0 through 25.0.8 Nextcloud Server versions 26.0.0 through 26.0.3 Nextcloud Server versions 27.0.0 through 27.0.0

Description The issue is related to improper access control in Nextcloud Server, which provides data storage for the Nextcloud open source cloud platform. An unauthenticated user could send a DAV request to reveal whether a calendar or an address book with a given identifier exists for the victim. This could allow a remote attacker to gain unauthorized access to protected information.

Recommendations For Nextcloud Server versions 25.0.0 through 25.0.8, update to version 25.0.9 or later. For Nextcloud Server versions 26.0.0 through 26.0.3, update to version 26.0.4 or later. For Nextcloud Server versions 27.0.0 through 27.0.0, update to version 27.0.1 or later.

Exploit

Fix

Improper Access Control

Weakness Enumeration

CWE-284

Related Identifiers

ALT-PU-2023-7785

ALT-PU-2025-1855

BDU:2023-05876

CVE-2023-39959

GHSA-G97R-8FFM-HFPJ

Affected Products

Alt Linux

Nextcloud Server

Red Os

References · 10

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/39xxx/CVE-2023-39959.json · Exploit
• https://github.com/nextcloud/server/pull/38747 · Patch
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-g97r-8ffm-hfpj · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2023-39959 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2023-39959 · Security Note
• https://bdu.fstec.ru/vul/2023-05876 · Security Note
• https://twitter.com/VulmonFeeds/status/1689740924442509312 · Twitter Post
• 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://redos.red-soft.ru/support/secure · Note
• https://hackerone.com/reports/1832126 · Note