CVE-2026-21726
5.3 · MEDIUMOverview
CVE-2026-21726 is a medium-severity vulnerability affecting grafana loki. It was published on April 15, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
The CVE-2021-36156 fix validates the namespace parameter for path traversal sequences after a single URL decode, by double encoding, an attacker can read files at the Ruler API endpoint /loki/api/v1/rules/{namespace}
Thanks to Prasanth Sundararajan for reporting this vulnerability.
Remediation
Check the references section for vendor advisories and patches from grafana. Update loki to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| grafana | loki | >= 0, < 3.6.4 | Affected |
Frequently Asked Questions
What is CVE-2026-21726?
CVE-2026-21726 is a medium-severity vulnerability affecting grafana loki. It was published on April 15, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-21726?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-21726?
Check the references section for vendor advisories and patches from grafana. Update loki to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-21726?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-21726 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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