CVE-2026-54560 Cloudreve: OAuth access tokens bypass scope enforcement due to missing client_id claim
Attackers can use low-scope OAuth tokens to access high-privilege APIs due to missing client_id claims, enabling unauthorized data access and modification.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-54560?
CVE-2026-54560 is a high-severity missing authorization vulnerability in cloudreve, published on 15 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
Cloudreve is a self-hosted file management and sharing system. From 4.12.0 until 4.16.1, Cloudreve's OAuth access tokens are issued without the OAuth client_id claim, so the JWT verifier does not load token scopes into request context and RequiredScopes treats the request like non-scoped session authentication, allowing a low-scope OAuth access token to call APIs requiring higher scopes such as file, share, workflow, user setting, WebDAV account, and potentially admin scopes. This issue is fixed in version 4.16.1.
Weakness: CWE-863
Which versions are affected by CVE-2026-54560?
5 open source packages ship an affected version, including github.com/cloudreve/Cloudreve/v4, github.com/cloudreve/Cloudreve and github.com/cloudreve/Cloudreve/v3.
| Package | Affected | Fixed in |
|---|---|---|
github.com/cloudreve/Cloudreve/v4 Go | From 4.0.0-20260114075425-bc6845bd742c | 4.0.0-20260606015557-ed20843dc3df |
github.com/cloudreve/Cloudreve/v4 Go | From 4.0.0-20260114075425-bc6845bd742c | 4.0.0-20260606015557-ed20843dc3df |
github.com/cloudreve/Cloudreve/v4 Go | From 4.0.0-20260114075425-bc6845bd742c | 4.0.0-20260606015557-ed20843dc3df |
github.com/cloudreve/Cloudreve Go | All versions | None |
github.com/cloudreve/Cloudreve/v3 Go | All versions | None |
How do I fix CVE-2026-54560?
Upgrade github.com/cloudreve/Cloudreve/v4 to 4.0.0-20260606015557-ed20843dc3df or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-54560 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-54560 exists.
Sources
Also known as GHSA-vgj4-345g-jcf8, GO-2026-6022.