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 a…

published 2026-09-18 52 d ago modified 2026-09-25 45 d ago also BIT-nextcloud-2026-68493 , EUVD-2026-82623

cvss: 3.1; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.2%; EPSS 0.2% chance of exploitation in 30 days, percentile 13%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

bitnami nextcloud 34.0.1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-68493 updated 2026-09-23 cvss 3.1

Nextcloud: Nextcloud: Information disclosure via identifier guessing

Red Hat All currently supported Red Hat products
not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 51 d ago (2026-09-18)

Exploit prediction

0.23% chance of exploitation in the next 30 days, higher than 13% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.0	3.1	CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
OSV	3.0	3.1	CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
bitnami	nextcloud	>=32.0.0, <34.0.1	34.0.1

Affected products

Nextcloud Server

Classification

Weakness

CWE-639 Authorization Bypass Through User-Controlled Key

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.

Summary