Summary
Today we are releasing Grafana 8.3.5 and 7.5.15. This patch release includes MEDIUM severity security fix for XSS for Grafana.
Release v.8.3.5, only containing security fixes:
Release v.7.5.15, only containing security fixes:
XSS (CVE-2022-21702)
On Jan. 16, an external security researcher, Jasu Viding contacted Grafana to disclose an XSS vulnerability in the way that Grafana handles data sources.
An attacker could serve HTML content through the Grafana datasource or plugin proxy and trick a user to visit this HTML page using a specially crafted link and execute a Cross-site Scripting (XSS) attack. The attacker could either compromise an existing datasource for a specific Grafana instance or either set up its own public service and instruct anyone to set it up in their Grafana instance.
We believe that this vulnerability is rated at CVSS 6.8 (CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:N/A:N).
Affected versions with MEDIUM severity
To be impacted, all of the following must be applicable:
For data source proxy:
- A Grafana instance running version v2.0.0-beta1 up to v8.3.4.
- A Grafana HTTP-based datasource configured with Server as Access Mode and a URL set.
- Attacker to be in control of the HTTP server serving the URL of above data source.
- A specially crafted link pointing at http://host/api/datasources/proxy/"data source id" and attacker somehow tricks a user of the above Grafana instance to click/visit the link.
- A user that’s already authenticated to above Grafana instance clicks on/visits the specially crafted link sent/provided by the attacker.
For plugin proxy:
- A Grafana instance running version v2.0.0-beta1 up to v8.3.4.
- A Grafana HTTP-based app plugin configured and enabled with a URL set.
- Attacker to be in control of the HTTP server serving the URL of above app.
- A specially crafted link pointing at http://host/api/plugin-proxy/"plugin id" and attacker somehow tricks a user of the above Grafana instance to click/visit the link.
- A user that’s already authenticated to above Grafana instance clicks on/visits the specially crafted link sent/provided by the attacker.
Backend plugin resource:
- A Grafana instance running version v7.0.0-beta1 up to v8.3.4.
- Attacker potentially needs to craft a custom plugin to be able to pull this off, but if an attacker can compromise/control the backend service that a backend plugin connects to, it might be possible to serve HTML content via the /api/plugins/"plugin Id"/resources* or /api/datasources/"id"/resources* routes.
- A specially crafted link pointing at /api/plugins/"plugin Id">/resources* or /api/datasources/"id"/resources* and attacker somehow tricks a user of the above Grafana instance to click/visit the link.
- A user that’s already authenticated to above Grafana instance clicks on/visits the specially crafted link sent/provided by the attacker.
Root Causes
Trigger
Reproduced and confirmed via this Golang app:
package main
import (
"fmt"
"log"
"net/http"
)
func main() {
http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
fmt.Fprintf(w, "<html><body><script>alert('XSS');</script></body></html>")
})
log.Fatal(http.ListenAndServe(":3011", nil))
}
A Prometheus datasource is configured in Grafana with URL http://localhost:3011.
When visitining http://localhost:3000/api/datasources/proxy/170 the scripts declared in the HTML page executes. Confirmed in both Chrome and Firefox.
Solutions and mitigations
All installations between Grafana v2.0.0-beta1 up to v8.3.4 should be upgraded as soon as possible.
Workarounds
Using a proxy, set a response header Content Security Policy: sandbox for the following routes:
/api/datasources/proxy*/api/plugin-proxy*/api/plugins/<pluginId>/resources*/api/datasources/<id>/resources*
Another possible mitigation is setting the response header Content-Disposition: attachment; “proxy.txt”. Confirmed in both Chrome and Firefox.
Timeline and postmortem
Here is a detailed timeline starting from when we originally learned of the issue. All times in UTC.
- 2022-01-16 16:19 Issue submitted by Jasu Viding
- 2022-01-17 14:40 CVSS score confirmed 6.8 at maximum and MEDIUM impact
- 2022-01-17 15:15 Vulnerability confirmed reproducible
- 2022-01-17 16:01 Begin mitigation for Grafana Cloud
- 2022-01-18 15:12 Similar report received
- 2022-01-19 09:57 CVE requested
- 2022-01-19 13:21 PR with fix opened
- 2022-01-19 19:53 GitHub issues CVE-2022-21702
- 2022-01-20 12:43 Second similar report received
- 2022-01-21 14:30 Private release planned for 2022-01-25, and public release planned for 2022-02-01
- 2022-01-25 12:00 Private release with patches
- 2022-02-01 12:00 During the public release process, we realized that private 7.x release was incomplete. Abort public release, send second private release to customers using 7.x
- 2022-02-08 13:00 Public release
Acknowledgement
We would like to thank Jasu Viding for responsibly disclosing the vulnerability.
Reporting security issues
If you think you have found a security vulnerability, please send a report to [email protected]. This address can be used for all of Grafana Labs' open source and commercial products (including, but not limited to Grafana, Grafana Cloud, Grafana Enterprise, and grafana.com). We can accept only vulnerability reports at this address. We would prefer that you encrypt your message to us by using our PGP key. The key fingerprint is
F988 7BEA 027A 049F AE8E 5CAA D125 8932 BE24 C5CA
The key is available from keyserver.ubuntu.com.
Security announcements
We maintain a security category on our blog, where we will always post a summary, remediation, and mitigation details for any patch containing security fixes.
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Impact
Should an existing data source connected to Grafana be compromised, it could be used to inappropriately gain access to other data sources connected to the same Grafana org.
Untrusted input is rendered as active markup in a victim's browser, which can run script in their session. Typical impact: session or credential theft, and actions taken as the user.
CVE-2022-21702 has a CVSS score of 6.8 (Medium). The vector is network-reachable, low privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (7.5.15, 8.3.5); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
Remediation advice
github.com/grafana/grafana to 7.5.15 or later; github.com/grafana/grafana to 8.3.5 or later
Kodem Kai can prioritize this vulnerability in your dependency tree and generate a fix recommendation.
Frequently Asked Questions
- What is CVE-2022-21702? CVE-2022-21702 is a medium-severity cross-site scripting (XSS) vulnerability in github.com/grafana/grafana (go), affecting versions >= 2.0.0-beta1, < 7.5.15. It is fixed in 7.5.15, 8.3.5. Untrusted input is rendered as active markup in a victim's browser, which can run script in their session.
- How severe is CVE-2022-21702? CVE-2022-21702 has a CVSS score of 6.8 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of github.com/grafana/grafana are affected by CVE-2022-21702? github.com/grafana/grafana (go) versions >= 2.0.0-beta1, < 7.5.15 is affected.
- Is there a fix for CVE-2022-21702? Yes. CVE-2022-21702 is fixed in 7.5.15, 8.3.5. Upgrade to this version or later.
- Is CVE-2022-21702 exploitable, and should I be worried? Whether CVE-2022-21702 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2022-21702 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2022-21702?
- Upgrade
github.com/grafana/grafanato 7.5.15 or later - Upgrade
github.com/grafana/grafanato 8.3.5 or later
- Upgrade