Field and document level security in Elasticsearch - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is field level security in Elasticsearch?

Field level security controls which fields a user can see or access in a document. It hides sensitive fields from users who don't have permission.

beginner

What does document level security do in Elasticsearch?

Document level security restricts access to entire documents based on user permissions. Users only see documents they are allowed to access.

intermediate

How do you define field level security in a role in Elasticsearch?

You specify allowed or denied fields using the field_security property inside the role's indices permissions. For example, "field_security": { "grant": ["title", "date"] } allows only those fields.

intermediate

How can document level security be implemented in Elasticsearch?

By using a query inside the role's indices permissions. This query filters documents a user can access, for example, "query": { "term": { "owner": "user1" } } shows only documents owned by user1.

beginner

Why is field and document level security important?

It protects sensitive data by limiting what users can see or access. This helps keep private information safe and enforces data privacy rules.

What does field level security control in Elasticsearch?

A Which fields a user can access in documents

B Which documents a user can access

C User authentication methods

D Index creation permissions

Field level security controls access to specific fields within documents.

How do you restrict documents a user can see in Elasticsearch?

A By modifying cluster settings

B By setting field grants

C By changing index settings

D Using a query in the role's indices permissions

Document level security uses a query filter in the role to restrict documents.

Which Elasticsearch role property is used to specify allowed fields?

A cluster_permissions

B document_security

C field_security

D index_patterns

The field_security property defines which fields are accessible.

What happens if a user lacks document level security permissions?

A They see no documents

B They see all documents

C They see only metadata

D They can edit documents

Without document level permissions, users cannot see any documents.

Why combine field and document level security?

A To speed up searches

B To protect both sensitive fields and restrict document access

C To allow anonymous access

D To backup data

Combining both ensures users see only allowed documents and fields.

Explain how field level security works in Elasticsearch roles.

Think about how you limit which parts of a document a user can see.

Describe how document level security filters documents for users.

Consider how you show only certain documents based on user identity.

Practice

1. What is the main purpose of field-level security in Elasticsearch?

easy

A. To restrict access to specific fields within documents

B. To encrypt the entire Elasticsearch index

C. To limit the number of documents returned in a query

D. To control user login credentials

Solution

1. Step 1: Understand field-level security concept

   Field-level security controls which fields in a document a user can see or query.

2. Step 2: Compare with other options

   Encryption and login control are unrelated to field-level security; limiting documents is document-level security.

3. Final Answer:

   To restrict access to specific fields within documents -> Option A

4. Quick Check:

   Field-level security = restrict fields [OK]

Hint: Field-level security hides fields, not whole documents [OK]

Common Mistakes:

• Confusing field-level with document-level security
• Thinking it encrypts data
• Assuming it controls user passwords

2. Which of the following is the correct syntax to define field-level security in an Elasticsearch role?

easy

A. "fields": ["title", "author"]

B. "field_security": { "deny": ["title", "author"] }

C. "field_security": { "grant": ["title", "author"] }

D. "field_access": { "allow": ["title", "author"] }

Solution

1. Step 1: Recall correct field-level security syntax

   Elasticsearch uses "field_security" with a "grant" array to specify allowed fields.

2. Step 2: Eliminate incorrect options

   "deny" is not valid here; "fields" and "field_access" are incorrect keys.

3. Final Answer:

   "field_security": { "grant": ["title", "author"] } -> Option C

4. Quick Check:

   Use "field_security" with "grant" for allowed fields [OK]

Hint: Use "field_security" with "grant" to allow fields [OK]

Common Mistakes:

• Using "deny" instead of "grant"
• Wrong key names like "fields" or "field_access"
• Confusing syntax with document-level security

3. Given this role definition snippet:

{
  "indices": [
    {
      "names": ["books"],
      "privileges": ["read"],
      "query": { "term": { "genre": "fiction" } },
      "field_security": { "grant": ["title", "author"] }
    }
  ]
}

What documents and fields will a user with this role see when querying the books index?

medium

A. All documents showing all fields

B. All documents showing only 'title' and 'author' fields

C. Only documents where genre is 'fiction' showing all fields

D. Only documents where genre is 'fiction' showing only 'title' and 'author' fields

Solution

1. Step 1: Analyze document-level security query

   The "query" limits documents to those with genre 'fiction'.

2. Step 2: Analyze field-level security grant

   Only "title" and "author" fields are visible due to "field_security".

3. Final Answer:

   Only documents where genre is 'fiction' showing only 'title' and 'author' fields -> Option D

4. Quick Check:

   Query filters docs + grant limits fields = Only documents where genre is 'fiction' showing only 'title' and 'author' fields [OK]

Hint: Query filters docs; field_security limits fields shown [OK]

Common Mistakes:

• Ignoring the query filter on documents
• Assuming all fields are visible
• Confusing document and field level restrictions

4. You defined this role snippet:

{
  "indices": [
    {
      "names": ["library"],
      "privileges": ["read"],
      "query": { "term": { "category": "science" } },
      "field_security": { "grant": ["title", "summary"] }
    }
  ]
}

But users report they see all documents and fields. What is the likely error?

medium

A. The query filter is incorrect or not applied properly

B. Field names in grant are misspelled

C. Privileges should include "write" to restrict fields

D. Role must include "manage" privilege for security to work

Solution

1. Step 1: Check query filter correctness

   If the query filter is malformed or ignored, document filtering won't happen.

2. Step 2: Verify field_security and privileges

   Field names look correct; "read" privilege is enough for filtering; "write" or "manage" not needed.

3. Final Answer:

   The query filter is incorrect or not applied properly -> Option A

4. Quick Check:

   Query filter controls docs; if ignored, all docs show [OK]

Hint: Check query syntax if document filtering fails [OK]

Common Mistakes:

• Assuming 'write' privilege needed for filtering
• Ignoring query filter syntax errors
• Thinking field names cause document filtering issues

5. You want to create a role that allows users to read only documents where status is active and see only the name and email fields. Which role definition snippet correctly implements this?

hard

A. {
"indices": [
{
"names": ["users"],
"privileges": ["read"],
"query": { "match": { "status": "active" } },
"field_security": { "deny": ["password"] }
}
]
}

B. {
"indices": [
{
"names": ["users"],
"privileges": ["read"],
"query": { "term": { "status": "active" } },
"field_security": { "grant": ["name", "email"] }
}
]
}

C. {
"indices": [
{
"names": ["users"],
"privileges": ["read"],
"query": { "term": { "status": "active" } },
"fields": ["name", "email"]
}
]
}

D. {
"indices": [
{
"names": ["users"],
"privileges": ["read"],
"query": { "term": { "status": "active" } }
}
]
}

Solution

1. Step 1: Verify document-level security query

   Using "term" query on "status" with "active" correctly filters documents.

2. Step 2: Verify field-level security syntax

   "field_security" with "grant" array specifying "name" and "email" fields is correct.

3. Step 3: Eliminate incorrect options

   { "indices": [ { "names": ["users"], "privileges": ["read"], "query": { "match": { "status": "active" } }, "field_security": { "deny": ["password"] } } ] } uses "deny" which is invalid; { "indices": [ { "names": ["users"], "privileges": ["read"], "query": { "term": { "status": "active" } }, "fields": ["name", "email"] } ] } uses wrong key "fields"; { "indices": [ { "names": ["users"], "privileges": ["read"], "query": { "term": { "status": "active" } } } ] } lacks field-level security.

4. Final Answer:

   Role with "query" term filter and "field_security" grant for "name" and "email" -> Option B

5. Quick Check:

   Use "query" for docs + "field_security" grant for fields [OK]

Hint: Use "query" for docs and "field_security" with "grant" for fields [OK]

Common Mistakes:

• Using "deny" instead of "grant" in field_security
• Using wrong keys like "fields" instead of "field_security"
• Omitting field-level security to restrict fields