Vulnerabilidades do Grafana Grafana OSS

Grafana's data source proxy did not apply role-based access control to write requests forwarded to Loki data sources. A user holding only the Viewer role on an affected Grafana instance could send POST, PUT and DELETE requests through the proxy to the Loki rules API (/loki/api/v1/rules), allowing them to create, modify and delete Loki alerting rules. Because those rules are stored by Loki rather than by Grafana, the change took effect for every user of that Loki data source, not only for the Viewer who made the request. Exploitation requires an authenticated Viewer account on the Grafana instance and a configured Loki data source; no other privileges are needed. Both Grafana OSS and Grafana Enterprise are affected. The defect is in Grafana's data source proxy; Loki itself is not vulnerable and does not need to be patched.

A stored cross-site scripting vulnerability in the Geomap panel's MapLibre base layer allows a user with the Editor role to execute arbitrary JavaScript in another user's session by hosting a malicious style configuration, enabling escalation to Org Admin.

Grafana OSS and Grafana Enterprise did not safely resolve symbolic links when extracting plugin archives. A crafted plugin archive can chain relative symbolic link entries to escape the plugin installation directory, writing arbitrary files and an executable backend binary outside that directory. The dropped executable runs with the privileges of the Grafana server process, resulting in remote code execution. Plugin archives are extracted before their signature is verified, so a valid plugin signature does not prevent the write. An operator can therefore be affected by installing a plugin that appears legitimate, as well as by installing a plugin from an arbitrary archive using grafana-cli, the GF_INSTALL_PLUGINS environment variable, or preinstall configuration. Grafana Enterprise is affected because it includes the same plugin extraction code as Grafana OSS.

Only self-managed Grafana instances with Auth Proxy authentication and identity caching enabled (sync_ttl greater than zero) are affected. The Auth Proxy cache key concatenated the username and forwarded identity attributes without a delimiter, so distinct identities could collide on one key. An authenticated user who shapes their own attributes to collide with a higher-privileged user's, while that user's cache entry is live, is authenticated as that user, up to Administrator (authentication bypass by spoofing).

An authenticated user with permission to create or edit alert rules can bypass datasource query authorization by marking an alert rule query as a server-side expression while referencing a real datasource UID (incorrect authorization). This can expose data accessible through Grafana's configured datasource credentials to users who lack permission to query that datasource.

An unauthenticated attacker can repeatedly call Grafana's OAuth login route with unique values, causing unbounded memory growth that can eventually exhaust memory and crash the Grafana instance (denial of service).

Several Grafana API endpoints, some of them unauthenticated, do not limit the size of the request body before processing it. An attacker can send very large payloads that force excessive memory allocation, potentially exhausting memory and causing a denial of service.

The public dashboard query endpoint does not limit request body size before processing, allowing unauthenticated attackers to trigger excessive memory allocation by sending arbitrarily large JSON payloads. This can lead to denial of service through memory exhaustion. No valid dashboard access token or authentication is required to exploit this vulnerability.

A user with Viewer permissions can use a path traversal in the Loki data source plugin to reach administrative Loki endpoints and read sensitive backend configuration and internal service information.