CVE-2026-55496 — github.com/cloudreve/Cloudreve/v4
Exposure of Sensitive Information to an Unauthorized ActorSummary
GET /api/v4/user/search is available to any logged-in user. The service calls userClient.SearchActive, but despite its name that method filters only by email/nickname keyword and never adds a StatusActive predicate — while the sibling lookups GetActiveByID and GetActiveByDavAccount, defined a few lines above it, do. Search hits are serialized at RedactLevelUser, which includes the email address.
A normal logged-in user can therefore enumerate and retrieve the email (plus nickname, avatar, creation time, redacted group, profile share-visibility) of inactive and banned accounts that an active-user directory is supposed to suppress. No global status interceptor compensates — the only User query interceptor is soft-delete, and inactive/banned rows are not soft-deleted.
Details
Root cause (verified at 26b6b10)
1. Route — logged-in + UserInfo.Read scope (routers/router.go):
user := v4.Group("user") // protected user group (login required)
user.GET("search",
middleware.RequiredScopes(types.ScopeUserInfoRead),
controllers.FromQuery[usersvc.SearchUserService](...), controllers.UserSearch)
The RequiredScopes check applies to scoped OAuth tokens; plain session requests are not gated by it — so any logged-in user reaches the search.
2. Service — 2-char keyword to SearchActive (service/user/info.go):
type SearchUserService struct { Keyword string `form:"keyword" binding:"required,min=2"` }
const resultLimit = 10
func (s *SearchUserService) Search(c *gin.Context) ([]*ent.User, error) {
return dep.UserClient().SearchActive(c, resultLimit, s.Keyword)
}
3. The bug — SearchActive has no status predicate (inventory/user.go):
func (c *userClient) SearchActive(ctx context.Context, limit int, keyword string) ([]*ent.User, error) {
ctx = context.WithValue(ctx, LoadUserGroup{}, true)
return withUserEagerLoading(ctx,
c.client.User.Query().
Where(user.Or(user.EmailContainsFold(keyword), user.NickContainsFold(keyword))).
Limit(limit), // <-- no user.StatusEQ(user.StatusActive)
).All(ctx)
}
Contrast the siblings immediately above:
func (c *userClient) GetActiveByID(...) { ... Where(user.ID(id)).Where(user.StatusEQ(user.StatusActive)) ... }
func (c *userClient) GetActiveByDavAccount(...) { ... Where(user.EmailEqualFold(email)).Where(user.StatusEQ(user.StatusActive)) ... }
withUserEagerLoading only eager-loads the group/passkey edges; it adds no status filter. Status values are active/inactive/manual_banned/sys_banned (ent/user/user.go).
4. No global status interceptor — User.Mixin() is CommonMixin{} (ent/schema/user.go), whose Interceptors() returns only softDeleteInterceptors (ent/schema/common.go). Inactive/banned users are not soft-deleted, so nothing filters them out at query time.
5. Results serialized with email (routers/controllers/user.go → service/user/response.go):
// UserSearch:
return user.BuildUserRedacted(item, user.RedactLevelUser, hasher)
// BuildUserRedacted:
if level == RedactLevelUser { user.Email = userRaw.Email } // email included
Secondary path: GET /api/v4/user/info/:id → GetUser uses GetByID (no status filter), and the controller picks RedactLevelUser for any non-anonymous caller (RedactLevelAnonymous only for anonymous). So a logged-in caller with an inactive/banned user's hashed ID also receives the email-bearing profile. (Less practical than search, since it needs the hashed ID rather than a 2-char keyword.)
Steps to reproduce (requires a live instance)
- Ensure a target account exists in
inactiveormanual_banned/sys_bannedstatus (e.g., an unconfirmed registration or a banned user). - As any logged-in user:
GET /api/v4/user/search?keyword=<>=2 chars of the target email/nick> Cookie: cloudreve-session=<attacker-session> - Observe the inactive/banned account in the results, including its
email. Expected: only active accounts appear (matching the method name and the siblingGetActive*behavior). Actual: inactive/banned accounts are returned with their email addresses.
Impact
Any logged-in user can enumerate and harvest the email addresses (and basic profile metadata) of inactive and banned accounts that active-user lookups intentionally hide. No account access, passwords, or 2FA secrets are exposed; the impact is PII leakage and user enumeration.
Remediation
- Add
Where(user.StatusEQ(user.StatusActive))toSearchActive(matchingGetActiveByID). - Apply the same active-status requirement to
GET /api/v4/user/info/:id, or fall back to anonymous-level redaction unless the target account is active. - Consider not returning email from directory search at all — display name + hashed ID is usually sufficient.
- Regression tests: searching a keyword that matches an inactive/banned account must return no result (or no email).
| Software | From | Fixed in |
|---|---|---|
github.com/cloudreve/Cloudreve/v4
|
- | 4.0.0-20260613023921-7e1289d55279 |
|
github.com/cloudreve/Cloudreve/v3
|
- | 3.0.0-20250225100611-da4e44b77af4.x |
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