CVE-2026-68493 | BDVDB-2026-376751 Detail

NextcloudServer

Description#

After guessing a 62^15 complex unique identifier, a malicious logged in user was able to retrieve a list of memberships for a circle they are not a member of.

Impact#

Per CVSS v3.0: confidentiality impact low, integrity impact none, availability impact none. Attack vector: network.

Weaknesses#

CWE-639 Authorization Bypass Through User-Controlled Key

References#

https://hackerone.com/reports/3484601

Exploit#

No public exploit known

History#

Version 12026-09-18Record published in the CVE List.

Published

Published: 2026-09-18
Last modified: 2026-09-18

Vendor information

Vendor: Nextcloud
Product: Server

All Nextcloud vulnerabilities

Score

3.1 Low

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 13.5.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Insecure Direct Object Reference

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
>= 32.0.0 and <= 34.0.0
Fixed
Not stated

Scoring System

CVSS v4.0

Not available

CVSS v3.1

Not available

CVSS v3.0

3.1 Low

CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Metric breakdown
Attack Vector	Network
Attack Complexity	High
Privileges Required	Low
User Interaction	None
Scope	Unchanged
Confidentiality	Low
Integrity	None
Availability	None

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).