How severe is CVE-2026-45284?

CVE-2026-45284 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-45284 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-45284?

CVE-2026-45284 affects Nextcloud User Oidc. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-45284?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-45284 have an EU (EUVD) identifier?

Yes. CVE-2026-45284 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33710.

When was CVE-2026-45284 published?

CVE-2026-45284 was published on 2026-06-01 and last updated on 2026-06-17.

CVE-2026-45284

CVE-2026-45284 is a medium-severity vulnerability in Nextcloud User Oidc with a CVSS 3.x base score of 4.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-284.

Key facts

Severity: Medium (CVSS 3.x base score 4.6)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-33710
Weakness: CWE-284
Affected product: Nextcloud User Oidc
Published: 2026-06-01
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-45284?: 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.
How severe is CVE-2026-45284?: CVE-2026-45284 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-45284 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-45284?: CVE-2026-45284 affects Nextcloud User Oidc. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-45284?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-45284 have an EU (EUVD) identifier?: Yes. CVE-2026-45284 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33710.
When was CVE-2026-45284 published?: CVE-2026-45284 was published on 2026-06-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:nextcloud:user_oidc:*:*:*:*:*:*:*:*

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