Vulnerabilities

Vulnerability · CVE-2026-45283

Nextcloud is an open source content collaboration platform.

Published Jun 1, 2026 · catalog updated Jul 22, 2026 · nextcloud server

Check if you run it

No confirmed exploitation is on record for CVE-2026-45283. EPSS is 0.36%. Act only if a listed version of nextcloud server is installed.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
Medium4.3
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.36%
Remediation
Advisory link
Affected products
cpe nextcloud/nextcloud server

Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.2, and 33.0.0 to before 33.0.1, the files_lock app did not properly validate the ownership of files when processing DAV lock and unlock requests. An authenticated user could lock or unlock files belonging to other users by targeting their absolute WebDAV paths. Additionally, lock tokens were disclosed to unauthorized callers in error responses, allowing attackers to remove token-based locks placed by other users' client applications. It is recommended that the Nextcloud Server is upgraded to 32.0.2 or 33.0.1. It is recommended that the Nextcloud Enterprise Server is upgraded to 31.0.14.4 or 32.0.2 or 33.0.1

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe nextcloud/nextcloud serverversion unspecified

How to fix CVE-2026-45283

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-45283. EPSS is 0.36%. Act only if a listed version of nextcloud server is installed.

Which versions are affected?

Affected version ranges are not on this record. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-287: Improper Authentication. EPSS 0.36%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Jun 1, 2026 · NIST NVD

    Detected

    Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.2, and 33.0.0 to before 33.0.1, the files_lock app did not properly validate the ownership of files when processing DAV lock and unlock requests. An authenticated user could lock or unlock files belonging to other users by targeting their absolute WebDAV paths. Additionally, lock tok

  2. Jul 22, 2026 · NIST NVD

    Updated

    Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.2, and 33.0.0 to before 33.0.1, the files_lock app did not properly validate the ownership of files when processing DAV lock and unlock requests. An authenticated user could lock or unlock files belonging to other users by targeting their absolute WebDAV paths. Additionally, lock tok

Sources

  • CVE.orgVulnerability recordCVE-2026-45283

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-45283

    30-day exploitation probability 0.4%

    first.org
  • NIST NVDVulnerability recordCVE-2026-45283

    Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.2, and 33.0.0 to before 33.0.1, the files_lock app did not properly validate the ownership of files when processing DAV lock and unlock requests. An authenticated u

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.