PT-2026-66493 · Tigera · Calico+2

Anthony Tam + 3 · CVE-2026-6540 · Published 2026-07-30 · Updated 2026-07-30

Mitre

CVSS v4.0

7.9

High

Base vector

AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:L

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.

Fix

Relative Path Traversal

Path traversal

Weakness Enumeration

CWE-23

CWE-22

Related Identifiers

CVE-2026-6540

Affected Products

Calico

Calico Cloud

Calico Enterprise

References · 5

• https://github.com/projectcalico/calico/pull/12532 · Patch
• https://github.com/projectcalico/calico/pull/12531 · Patch
• https://github.com/projectcalico/calico/pull/12533 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-6540 · Security Note
• https://tigera.io/security-bulletins/tta-2026-005 · Vendor Advisory