CVE-2026-45159
LowCVSS 3.5Exploitation Probability (EPSS)
Low risk10th percentile - higher than 10% of all known CVEs
Summary
In Nextcloud from versions 1.15.0 to before 1.15.4, 1.16.0 to before 1.16.3, 1.17.0 to before 1.17.1, and 1.18.0 to before 1.18.1, a malicious user with access to an end-to-end encrypted files drop link could drop files into other encrypted folders of the share owner. Reading and modifying other files was not possible.
Risk Assessment
An attacker can place unwanted files into other encrypted folders, potentially leading to clutter or data integrity issues.
Recommendation
Update Nextcloud to version 1.15.4, 1.16.3, 1.17.1, 1.18.1, or 2.0.0-rc.7.
Original NVD description (English source)
Nextcloud is an open source content collaboration platform. From versions 1.15.0 to before 1.15.4, 1.16.0 to before 1.16.3, 1.17.0 to before 1.17.1, and 1.18.0 to before 1.18.1, a malicious user with access to an end-to-end encrypted files drop link was able to also drop files into other end-to-end encrypted folders of the share owner. Reading and modifying of other files was not possible. This issue has been patched in versions 1.15.4, 1.16.3, 1.17.1, 1.18.1, and 2.0.0-rc.7.