Bug 2484569 (CVE-2026-45282)

Summary: CVE-2026-45282 nextcloud: Nextcloud Server: Information disclosure via circumventing link share protections
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
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. An authenticated attacker, by knowing a share token and a document ID, could access attachments of link shares. This circumvents password protection or download restrictions, leading to the disclosure of sensitive information from attachments.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2484572, 2484573    
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Description OSIDB Bzimport 2026-06-03 22:34:51 UTC 
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, an authenticated attacker can access attachments of link shares when knowing the share token, circumventing password protection or download restrictions. It is applicable to any file that is shared directly, as the attacker only needs to know a documentId they own, apart of the mentioned share token. For shared folders the attacker has to know or guess a documentId of a file that is included inside the folder, making it much harder to exploit. The attacker can only extract an attachments, but not the file shared file or folder itself. 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, 29.0.16.16, 28.0.14.17 or 27.1.11.5