Vulnerability · Published Jul 31, 2026 · Assigned by GitHub_M
CVE-2026-55499Cloudreve: Broken access control in file event stream leaks activity events for unshared siblings to single-file share recipients
Medium 4.3
In plain English
A medium-severity incorrect authorization in cloudreve from cloudreve. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, a single-file share event-stream subscription resolves the share root to the owner’s parent folder and subscribes to that folder topic, allowing an authenticated share recipient to receive names, paths, rename targets, event types, and hashed identifiers for unshared sibling files and folders. This issue is fixed in version 4.17.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/cloudreve/Cloudreve | no fix listed | GO-2026-6102 |
| Go | github.com/cloudreve/Cloudreve/v3 | no fix listed | GHSA-w8x7-h2px-xmq8 |
| Go | github.com/cloudreve/Cloudreve/v3 | no fix listed | GO-2026-6102 |
| Go | github.com/cloudreve/Cloudreve/v4 | 4.0.0-20260613030215-0b00dd308f13 | GHSA-w8x7-h2px-xmq8 |
| Go | github.com/cloudreve/Cloudreve/v4 | 4.0.0-20260613030215-0b00dd308f13 | GO-2026-6102 |
Affected products (as reported)
Weakness: CWE-863 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N