8.8

CVE-2026-45284: nextcloud security-advisories Improper Access Control

CVSS: 8.8v3.1HighAnalyzed
Published 01-06-2026Last modified 02-06-2026
Open JSON

Vulnerability summary

CVE-2026-45284 is a high (CVSS 8.8) Improper Access Control vulnerability in nextcloud security-advisories. EPSS estimates a 0.36% chance of exploitation in the next 30 days, higher than 28.5% of scored vulnerabilities.

Overall risk
35/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.8/10
010
High · v3.1 (NVD)
EPSS score
0.36%
0%100%
Low · +0.17 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Timeline

  1. 01-06-2026
    PublishedVulnerability first disclosed.
  2. 02-06-2026
    Last modifiedVulnerability information updated.

Description

Nextcloud is an open source content collaboration platform. From version 1.3.6 to before version 8.4.0, an improper check allowed users that where provided by LDAP to still authenticate towards user OIDC after they where deleted. This issue has been patched in version 8.4.0.

CVSS metrics

2 scores · 2 sources · 1 version

EPSS trend

Probability

0.36%

Chance of exploitation in the next 30 days

Percentile

29%

Versus all other CVEs

30-day change

+0.17 pp

From 0.19% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.36%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Nextcloud2 products

1 vendor · 2 products

References

3 links