Nextcloud User OIDC up to 8.3.x access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.1$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Nextcloud User OIDC up to 8.3.x. This impacts an unknown function. The manipulation leads to access control. This vulnerability is traded as CVE-2026-45284. It is possible to initiate the attack remotely. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Nextcloud User OIDC up to 8.3.x. It has been rated as critical. This issue affects an unknown functionality. The manipulation with an unknown input leads to a access control vulnerability. Using CWE to declare the problem leads to CWE-284. The product does not restrict or incorrectly restricts access to a resource from an unauthorized actor. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. The identification of this vulnerability is CVE-2026-45284 since 05/11/2026. The exploitation is known to be difficult. The attack may be initiated remotely. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1068 according to MITRE ATT&CK.

Upgrading to version 8.4.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 6.1

VulDB Base Score: 5.0
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔒

CNA Base Score: 4.6
CNA Vector (GitHub_M): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-284 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: User OIDC 8.4.0
Patch: github.com

Timelineinfo

05/11/2026 CVE reserved
06/01/2026 +21 days Advisory disclosed
06/01/2026 +0 days VulDB entry created
06/07/2026 +6 days VulDB entry last update

Sourcesinfo

Advisory: GHSA-79xf-ffj8-96fm
Status: Confirmed

CVE: CVE-2026-45284 (🔒)
GCVE (CVE): GCVE-0-2026-45284
GCVE (VulDB): GCVE-100-367739

Entryinfo

Created: 06/01/2026 21:51
Updated: 06/07/2026 16:53
Changes: 06/01/2026 21:51 (66), 06/07/2026 16:53 (11)
Complete: 🔍
Cache ID: 216::103

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