Vulnerabilidades de Grafana

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.

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).

Grafana Alloy’s prometheus.operator.servicemonitors component allows a user who can create or modify ServiceMonitor resources in a watched namespace to specify an arbitrary local file through bearerTokenFile. Alloy reads the file and sends its contents as a bearer token to an attacker-controlled scrape endpoint. This may disclose files accessible to the Alloy process, including its projected Kubernetes service account token, potentially granting the attacker Alloy’s Kubernetes permissions. Exploitation requires ServiceMonitor write access and lower privileges than Alloy’s service account.

Note: The CVE and blog post don't exist because we determined this is actually a cloud-only issue. Access Controls are “Broken” when a user can access resources they are not authorized to access. An attacker can bypass any access control mechanisms in a web application, and gain unauthorized access to resources that are not available with their permissions. Broken access control can allow attackers to: Access resources only accessible to certain users, thus allowing unauthorized access to data Perform operations on behalf of other users, leading to account takeovers in the worst cases Attempt privilege escalation Attempt to take over an account

Loki queries with large limits can cause large memory allocations which can impact the availability of the service, depending on its deployment strategy.

A confused-deputy flaw in Grafana MCP Server allows an unauthenticated remote attacker to exfiltrate the server's environment-configured Grafana service-account token by supplying a crafted X-Grafana-URL request header. This also enables SSRF against arbitrary internal services, including cloud metadata endpoints.

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.