CVE-2026-6540
7.5 · HIGHOverview
CVE-2026-6540 is a high-severity vulnerability affecting tigera calico. It was published on July 30, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
Calico's Application Layer Policy (disabled by default), which enforces HTTP rules through Dikastes, fails to perform URL path normalization. As a result, HTTP requests using path-traversal segments, encoded slashes, or repeated slashes are not correctly evaluated by Prefix path rules. Dikastes authorizes the request under the permitted prefix while the downstream workload or a fronting proxy normalizes the path and serves the restricted endpoint. An attacker with network access and no special RBAC can potentially reach HTTP endpoints the policy was intended to restrict.
Remediation
Check the references section for vendor advisories and patches from tigera. Update calico 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 |
|---|---|---|---|
| tigera | calico | >= 0, < 3.21.7 | Affected |
Frequently Asked Questions
What is CVE-2026-6540?
CVE-2026-6540 is a high-severity vulnerability affecting tigera calico. It was published on July 30, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-6540?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-6540?
Check the references section for vendor advisories and patches from tigera. Update calico 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-2026-6540?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-6540 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
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