GHSA-p4mj-98mv-xq26: Gitea: Private Repository Existence Disclosure via go-get Meta Endpoint

| Field | Value | |-------|-------| | Affected File | routers/web/repo/githttp.go, services/context/repo.go | | Affected Functions | httpBase(), EarlyResponseForGoGetMeta() | | Affected Lines | githttp.go:63–66, services/context/repo.go:374–396 | | Prerequisite | None — fully unauthenticated | Description Gitea implements a special behavior for requests containing the ?go-get=1 query parameter. This parameter is sent by the Go toolchain (go get, go install) to discover VCS metadata for module imports. When Gitea detects this parameter in the HTTP request path for a repository, it bypasses the normal authentication and authorization stack and returns an HTTP 200 response containing <meta name="go-import"> and <meta name="go-source"> tags — regardless of whether: - The repository is private - The requesting user is authenticated - The requesting user has any permission on the repository The entry point is routers/web/repo/githttp.go:63–66: func httpBase(ctx *context.Context, optGitService ...string) *serviceHandler { reponame := strings.TrimSuffix(ctx.PathParam("reponame"), ".git") if ctx.FormString("go-get") == "1" { context.EarlyResponseForGoGetMeta(ctx) return nil // ← returns before any auth or permission check } ... The EarlyResponseForGoGetMeta function (services/context/repo.go:379–396) is called unconditionally, and the function's own docstring documents the intended behavior: // EarlyResponseForGoGetMeta responses appropriate go-get meta with status 200 // if user does not have actual access to the requested repository, // or the owner or repository does not exist at all. // This is particular a workaround for "go get" command which does not respect // .netrc file. func EarlyResponseForGoGetMeta(ctx *Context) { username := ctx.PathParam("username") reponame := strings.TrimSuffix(ctx.PathParam("reponame"), ".git") ... ctx.PlainText(http.StatusOK, htmlMeta) // ← HTTP 200, no auth check } The function also appears at services/context/repo.go:444, 516, 5