CVE-2026-45691

MEDIUM EPSS 20.7%
Published Jun 1, 20264w ago · Modified Jun 17, 20261w ago
5.9 CVSS 3.1
Medium
Find Similar
Published Jun 1, 2026 4w ago
Last Modified Jun 17, 2026 1w ago

Description

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, a pre-2FA session cookie (created after successful password authentication but before TOTP completion) could be reused as a Bearer token to authenticate against DAV endpoints, granting read/write access and bypassing mandatory two-factor authentication. It is recommended that the Nextcloud Server is upgraded to 33.0.3 or 32.0.9. It is recommended that the Nextcloud Enterprise Server is upgraded to 33.0.3, 32.0.9, 31.0.14.5, 30.0.17.9 or 29.0.16.16

CVSS Details

Base Score
5.9
Exploitability
1.6
Impact
4.2
Vector string
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N
Attack Vector Network
Attack Complexity High
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality Low
Integrity High
Availability None

Threat Intelligence

EPSS Exploit Probability
20.7% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 1

CWE-287 Improper Authentication Authentication

Affected Products 7

VendorProductVersionRange
nextcloudnextcloud_server*≥32.0.0  –  <32.0.9
nextcloudnextcloud_server*≥33.0.0  –  <33.0.3
nextcloudnextcloud_server*≥29.0.0  –  <29.0.16.16
nextcloudnextcloud_server*≥30.0.0  –  <30.0.17.9
nextcloudnextcloud_server*≥31.0.0  –  <31.0.14.5
nextcloudnextcloud_server*≥32.0.0  –  <32.0.9
nextcloudnextcloud_server*≥33.0.0  –  <33.0.3

References 3

  • github.com https://github.com/nextcloud/security-advisories/security/advisories/GHSA-mp6x-g55j-w9jw
    Vendor Advisory
  • github.com https://github.com/nextcloud/server/pull/59758
    Issue TrackingPatch
  • hackerone.com https://hackerone.com/reports/3573399
    Permissions Required

Remediation

  • github.com https://github.com/nextcloud/server/pull/59758
    Issue TrackingPatch