Nextcloud ServerApplication · Nextcloud
CVE-2026-45282
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedNextcloud 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
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisThe application fails to correctly restrict what a user can do or reach, so functions or resources are available to people who should not have them. Attackers simply probe for the paths where the check is missing or wrong. The fix is to enforce access-control decisions consistently on every request, evaluated against the acting user rather than assumed from context.
General guidance for the improper access control class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Nextcloud ServerApplication
>= 32.0.0, < 32.0.9>= 33.0.0, < 33.0.3>= 27.0.0, < 27.1.11.5>= 28.0.0, < 28.0.14.17>= 29.0.0, < 29.0.16.16>= 30.0.0, < 30.0.17.9>= 31.0.0, < 31.0.14.5CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped27.1.11.528.0.14.1729.0.16.16
Upgrade to 32.0.9 (if on 32.x), 33.0.3 (if on 33.x), 28.0.14.17 (if on 28.x), or 27.1.11.5 (if on 27.x)
- 1. Create a full backup of your Nextcloud data directory, database, and configuration files
- 2. Put Nextcloud into maintenance mode via occ maintenance:mode --on
- 3. Update Nextcloud using your package manager (e.g., apt update && apt upgrade for Ubuntu/Debian, or yum update for RHEL/CentOS)
- 4. Alternatively, run: occ upgrade after manually downloading the new package
- 5. Clear caches: occ cache:clear
- 6. Disable maintenance mode: occ maintenance:mode --off
- 7. Verify the upgrade by checking the version at Settings > Administration > Overview
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-45282 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-45282 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.
A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.
- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
- No spam, self-promotion, credentials, or personal data