4.3Medium
CVE-2026-55499
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.
What this means for your business
- An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.2% chance of attack attempts being seen in the next 30 days, ranking above 15% of all known flaws.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.
Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N- Weakness
- CWE-863
- Assigned by
- security-advisories@github.com
Dates
- Published
- 2026-07-31
- Last modified
- 2026-09-08
- Sources
- NVD
References
- https://github.com/cloudreve/cloudreve/commit/0b00dd308f132d6e6e8476857ef79f4865600bbc
- https://github.com/cloudreve/cloudreve/releases/tag/4.17.0
- https://github.com/cloudreve/cloudreve/security/advisories/GHSA-w8x7-h2px-xmq8
- https://github.com/cloudreve/cloudreve/security/advisories/GHSA-w8x7-h2px-xmq8