4.3Medium
CVE-2026-55495
Cloudreve is a self-hosted file management and sharing system. Prior to 4.17.0, the WOPI PUT_RELATIVE handler passes X-WOPI-SuggestedTarget to URI.JoinRaw as a path rather than a filename, allowing slash and dot-dot segments to escape the source file directory and create or conditionally overwrite files elsewhere in the same owner account. 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 0.3% chance of attack attempts being seen in the next 30 days, ranking above 18% 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?
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Scoring
- CVSS
- 4.3 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N- Weakness
- CWE-22
- 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/7968e50429efab40ffa8f57fecdfbd5a73d23630
- https://github.com/cloudreve/cloudreve/releases/tag/4.17.0
- https://github.com/cloudreve/cloudreve/security/advisories/GHSA-49h3-cwhj-4737
- https://github.com/cloudreve/cloudreve/security/advisories/GHSA-49h3-cwhj-4737