CVE-2021-41174 XSS vulnerability allowing arbitrary JavaScript execution

What is CVE-2021-41174?

CVE-2021-41174 is a medium-severity cross-site scripting vulnerability in Grafana Grafana, published on 3 Nov 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Grafana is an open-source platform for monitoring and observability. In affected versions if an attacker is able to convince a victim to visit a URL referencing a vulnerable page, arbitrary JavaScript content may be executed within the context of the victim's browser. The user visiting the malicious link must be unauthenticated and the link must be for a page that contains the login button in the menu bar. The url has to be crafted to exploit AngularJS rendering and contain the interpolation binding for AngularJS expressions. AngularJS uses double curly braces for interpolation binding: {{ }} ex: {{constructor.constructor(‘alert(1)’)()}}. When the user follows the link and the page renders, the login button will contain the original link with a query parameter to force a redirect to the login page. The URL is not validated and the AngularJS rendering engine will execute the JavaScript expression contained in the URL. Users are advised to upgrade as soon as possible. If for some reason you cannot upgrade, you can use a reverse proxy or similar to block access to block the literal string {{ in the path.

Weakness: CWE-79

Which versions are affected by CVE-2021-41174?

3 open source packages ship an affected version, including @grafana/data and grafana. It affects 1 product.

Products include Grafana Grafana.

How do I fix CVE-2021-41174?

Upgrade @grafana/data to 8.2.3 or later.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2021-41174 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-41174 exists.

Public exploit code: 1 Nuclei template.

Other vulnerabilities in Grafana Grafana

• CVE-2021-43798 Grafana Path Traversal Exploited High 7.5
• CVE-2025-41115 Incorrect privilege assignment Critical 10.0
• CVE-2022-39328 Grafana vulnerable to race condition allowing privilege escalation Critical 9.8
• CVE-2022-28660 Auth bypass in n/a Critical 9.8
• CVE-2022-26148 Information disclosure in n/a Critical 9.8

All Grafana Grafana vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as BIT-grafana-2021-41174, GHSA-3j9m-hcv9-rpj8, UBUNTU-CVE-2021-41174.