CVE-2026-56443

Ein Angreifer kann mehrere Schwachstellen in Gitea ausnutzen, um beliebigen Programmcode auszuführen, erweiterte Berechtigungen zu erlangen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, sensible Informationen offenzulegen, Sitzungen zu übernehmen oder wiederzuverwenden oder einen Denial-of-Service-Zustand auszulösen.

## Summary After [PR #37118](https://github.com/go-gitea/gitea/pull/37118) / **CVE-2026-25714** (`fix: Unify public-only token filtering in API queries and repo access checks`, merged 2026-05-18, backport `#37773` to 1.26.2 — the May 2026 unification pass for public-only token filtering, reporter Medoedus per the 1.26.2 release notes), the `public-only` PAT scope is still bypassable on **Repository** and **Package** scope categories when the owner's `Visibility = Limited` (instance-internal). The sibling `Org` / `User` / `ActivityPub` cases in the same `checkTokenPublicOnly` switch correctly reject Limited owners via `!Visibility.IsPublic()`. The Repository / Package cases use `repo.IsPrivate` or `Owner.Visibility.IsPrivate()`, both of which return `false` for `VisibleTypeLimited` — so a `public-only` PAT strictly exceeds anonymous reach on a Limited owner. Tested on `gitea/gitea:1.26.2`. The decisive marker is that PR #37118's unification IS applied in the version under test (User-category PROBE returns `403 "token scope is limited to public users"`). Despite that, the Repository-category PROBE on the same Limited owner with the same PAT returns `200` and serves content. ## Affected entry points (4 spots) | File:Line | Function | Affected surface | |---|---|---| | `routers/api/v1/api.go:292` | `checkTokenPublicOnly` Package case | API v1 packages | | `routers/api/packages/api.go:76` | `reqPackageAccess` middleware | All 24 native package registries (`/api/packages/<type>/...`) | | `services/context/api.go` | `TokenCanAccessRepo` helper | All API v1 Repository-category endpoints — content, issues, PRs, releases, labels, milestones, etc. | | `services/context/permission.go:32` | `CheckTokenScopes` (called via `CheckRepoScopedToken`) | Web download endpoints `/raw`, `/media`, `/attachments`. LFS routes (`services/lfs/server.go:470/472`, `services/lfs/locks.go:62/151/216/284`) also chain through this helper. | All four sinks check `repo.IsPrivate` or `Owner.Visibility.IsPrivate()` only. `VisibleTypeLimited` falls through. ```go // modules/structs/visible_type.go func (vt VisibleType) IsPrivate() bool { return vt == VisibleTypePrivate } // line 39-40 func (vt VisibleType) IsLimited() bool { return vt == VisibleTypeLimited } // line 33-34 ``` ## Same-file evidence (`routers/api/v1/api.go:246-299` after PR #37118) ```go case auth_model.AccessTokenScopeCategoryOrganization: orgPrivate := ... && !ctx.Org.Organization.Visibility.IsPublic() // !IsPublic ✓ case auth_model.AccessTokenScopeCategoryUser: if ... && !ctx.ContextUser.Visibility.IsPublic() { ... } // !IsPublic ✓ case auth_model.AccessTokenScopeCategoryActivityPub: if ... && !ctx.ContextUser.Visibility.IsPublic() { ... } // !IsPublic ✓ case auth_model.AccessTokenScopeCategoryPackage: if ctx.Package != nil && ctx.Package.Owner.Visibility.IsPrivate() { // IsPrivate ONLY ✗ ctx.APIError(http.StatusForbidden, "token scope is limited to public packages") return } ``` `TokenCanAccessRepo` (`services/context/api.go`) reduces to `!repo.IsPrivate`: ```go // A public-only token cannot reach a private repo; any other token is unrestricted by this check. func (ctx *APIContext) TokenCanAccessRepo(repo *repo_model.Repository) bool { return repo == nil || !ctx.PublicOnly || !repo.IsPrivate } ``` `CheckTokenScopes` (`services/context/permission.go:32`): ```go if publicOnly && repo != nil && repo.IsPrivate { ctx.HTTPError(http.StatusForbidden) return } ``` ## PoC (Docker e2e VERIFIED on `gitea/gitea:1.26.2`, 2026-06-05) Full script in the report (`run-poc.sh`). Setup: 1. Create user `limuser`. `PATCH /api/v1/admin/users/limuser` with body `{"visibility":"limited", ...}` — response confirms `"visibility":"limited"`. 2. Upload a generic package as `limuser`: `PUT /api/packages/limuser/generic/secretpkg/1.0.0/secret.txt` with body `secret-content-internal-only` → `201`. 3. Create user `attacker`. 4. Mint PAT for `attacker` with `scopes=["read:package","read:user","read:repository","public-only"]`. Result on `gitea/gitea:1.26.2` — nine PROBEs: ``` PROBE A (download package via attacker PAT) HTTP=200 Body: secret-content-internal-only PROBE C (read README of limuser's PUBLIC repo) HTTP=200 Body: {"name":"README.md", ...} PROBE F (sanity — User category, same PAT, same owner) HTTP=403 Body: {"message":"token scope is limited to public users"} PROBE G (Repository category, same PAT, same owner) HTTP=200 Body: {"name":"README.md", ...} ← bypass PROBE H (list limuser's repos, User category) HTTP=403 Body: {"message":"token scope is limited to public users"} PROBE M (git HTTPS smart protocol — info/refs) HTTP=200 Body: 001e# service=git-upload-pack ... HEAD ... ← full clone enabled PROBE N (write attempt: POST contents/hacked.txt) HTTP=403 Body: {"message":"user should have a permission to write to the target branch"} Integrity:N confirmed PROBE O (Limited ORG — same bypass class) Org category : HTTP=403 {"message":"token scope is limited to public orgs"} Repo category : HTTP=200 README content ← bypass Anonymous baseline (no auth) on every above endpoint: HTTP=401/404 ``` Gitea's own server error string in PROBE F / H / O — *"token scope is limited to public users"* / *"public orgs"* — is the explicit declaration of intent. Repository / Package category violates that intent on the same Limited owner. ## Why this is not a duplicate of CVE-2026-25714 CVE-2026-25714 / PR #37118 (the May 2026 unification pass for public-only token filtering, merged 2026-05-18, backported to 1.26.2 via PR #37773) realigned `checkTokenPublicOnly`'s Org / User / ActivityPub cases on `!Visibility.IsPublic()` and introduced the `TokenCanAccessRepo` helper for the Repository / Issue / Notification cases. PROBE F on `1.26.2` returns `403 "token scope is limited to public users"` for the User category — i.e. PR #37118's unification IS in effect on the version under test. The Repository / Package leak occurs *after* that fix; the Limited gap is the next residual issue on the same hygiene effort (the Package case was not touched, and `TokenCanAccessRepo` reduces to `!repo.IsPrivate` without consulting owner visibility), not the same bug. ## Suggested fix (4 spots, 1-line shape each) ```go // routers/api/v1/api.go:292 (checkTokenPublicOnly Package case) - if ctx.Package != nil && ctx.Package.Owner.Visibility.IsPrivate() { + if ctx.Package != nil && !ctx.Package.Owner.Visibility.IsPublic() { // routers/api/packages/api.go:76 (reqPackageAccess middleware) - if ctx.Package != nil && ctx.Package.Owner.Visibility.IsPrivate() { + if ctx.Package != nil && !ctx.Package.Owner.Visibility.IsPublic() { // services/context/api.go (TokenCanAccessRepo helper) - return repo == nil || !ctx.PublicOnly || !repo.IsPrivate + return repo == nil || !ctx.PublicOnly || + (!repo.IsPrivate && repo.Owner != nil && repo.Owner.Visibility.IsPublic()) // services/context/permission.go:32 (CheckTokenScopes) - if publicOnly && repo != nil && repo.IsPrivate { + if publicOnly && repo != nil && + (repo.IsPrivate || (repo.Owner != nil && !repo.Owner.Visibility.IsPublic())) { ``` This aligns the Repository / Package categories with the User / Org / ActivityPub siblings already shipped in PR #37118. ## Reporter JebeenLee

Gitea: Token public-only scope bypassed on Limited-visibility owners (Repository + Package categories) — residual after CVE-2026-25714 / PR #37118 in gitea.dev