[Security] 9.1.2 release notes (#2512)

Resolves #2511: adds the
9.1.2 Security and Endpoint release notes.

Preview:
[9.1.2](https://docs-v3-preview.elastic.dev/elastic/docs-content/pull/2512/release-notes/elastic-security)

---------

Co-authored-by: Gabriel Landau <[email protected]>
Co-authored-by: natasha-moore-elastic <[email protected]>
Co-authored-by: natasha-moore-elastic <[email protected]>

Author: 3 people

release-notes/elastic-security/index.md

@@ -27,6 +27,20 @@ To check for security updates, go to [Security announcements for the Elastic sta
 
 % *
 
+## 9.1.2 [elastic-security-9.1.2-release-notes]
+
+### Features and enhancements [elastic-security-9.1.2-features-enhancements]
+* Adds Automatic Import documentation links for users in log description and the error message so that users have better access to the data types that are valid [#229375]({{kib-pull}}229375).
+* To help identify which parts of `elastic-endpoint.exe` are using a significant amount of CPU, {{elastic-defend}} on Windows can now include CPU profiling data in diagnostics. To request CPU profiling data using the command line, refer to [{{agent}} command reference](/reference/fleet/agent-command-reference.md#_options). To request CPU profiling data using {{kib}}, check the **Collect additional CPU metrics** box when requesting {{agent}} diagnostics.
+* Improves {{elastic-defend}} malware scan queue efficiency on Windows by not blocking scan requests when an oplock for the file being scanned cannot be acquired.
+* Allows {{elastic-defend}} to automatically recover in some situations when it loses connectivity with {{agent}}.
+
+### Fixes [elastic-security-9.1.2-fixes]
+* Fixes privileged user monitoring index sync in non-default {{kib}} spaces [#230420]({{kib-pull}}230420).
+* Only creates a privileged user monitoring default index source if one doesn't currently exist [#229693]({{kib-pull}}229693).
+* Fixes a race condition in {{elastic-defend}} that may occasionally result in corrupted process command lines on Windows. When this occurs, `process.command_line`, `process.args_count` and `process.args` may be incorrect, leading to false positives.
+* Due to an issue in macOS, {{elastic-defend}} would sometimes send network events without `user.name` populated. {{elastic-defend}} will now identify these events and populate `user.name` if necessary.
+
 ## 9.1.1 [elastic-security-9.1.1-release-notes]
 
 ### Features and enhancements [elastic-security-9.1.1-features-enhancements]