Bug 2483830 (CVE-2026-45690)

Summary: CVE-2026-45690 nextcloud-server: Nextcloud Server: Authentication bypass allows unauthorized access by circumventing two-factor authentication.
Product: [Other] Security Response Reporter: Jon Moroney <jmoroney>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Nextcloud Server. This vulnerability allows a remote attacker, with knowledge of a user's password, to bypass two-factor authentication (2FA) protections. When a user attempts to log in with valid credentials on a 2FA-enabled account, a temporary session token is generated before the second factor challenge. This token can be extracted and replayed using HTTP Basic Authentication, leading to unauthorized access to authenticated parts of the system.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2483840, 2483841    
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Description Jon Moroney 2026-06-01 21:43:08 UTC
HASH(0x55c1f40d7aa0)