Add SECURITY.md

Also modify bug report issue template to make it clear it's
not to be used to report security vulnerabilities.

Fixes eclipse-theia#8795

Signed-off-by: Marc Dumais <[email protected]>

.github/ISSUE_TEMPLATE/bug_report.md

@@ -1,5 +1,5 @@
 ---
-name: Bug Report
+name: Bug Report (except security vulnerabilities)
 about: Create a report to help us improve
 ---
 

SECURITY.md

@@ -0,0 +1,49 @@
+<!--- https://www.eclipse.org/security/ --->
+_ISO 27005 defines vulnerability as:
+ "A weakness of an asset or group of assets that can be exploited by one or more threats."_
+
+## The Eclipse Security Team
+
+The Eclipse Security Team provides help and advice to Eclipse projects
+on vulnerability issues and is the first point of contact
+for handling security vulnerabilities.
+Members of the Security Team are committers on Eclipse Projects
+and members of the Eclipse Architecture Council.
+
+Contact the [Eclipse Security Team](mailto:[email protected]).
+
+**Note that, as a matter of policy, the security team does not open attachments.**
+
+## Reporting a Security Vulnerability
+
+Vulnerabilities can be reported either via email to the Eclipse Security Team
+or directly with a project via the Eclipse Foundation's Bugzilla instance.
+
+The general security mailing list address is [email protected].
+Members of the Eclipse Security Team will receive messages sent to this address.
+This address should be used only for reporting undisclosed vulnerabilities;
+regular issue reports and questions unrelated to vulnerabilities in Eclipse software
+will be ignored.
+Note that this email address is not encrypted.
+
+The community is also encouraged to report vulnerabilities using the
+[Eclipse Foundation's Bugzilla instance](https://bugs.eclipse.org/bugs/enter_bug.cgi?product=Community&component=Vulnerability%20Reports&keywords=security&groups=Security_Advisories).
+Note that you will require an Eclipse Foundation account to create an issue report,
+but by doing so you will be able to participate directly in the resolution of the issue.
+
+Issue reports related to vulnerabilities must be marked as "committers-only",
+either automatically by clicking the provided link, by the reporter,
+or by a committer during the triage process.
+Note that issues marked "committers-only" are visible to all Eclipse committers.
+By default, a "committers-only" issue is also accessible to the reporter
+and individuals explicitly indicated in the "cc" list.
+
+## Disclosure
+
+Disclosure is initially limited to the reporter and all Eclipse Committers,
+but is expanded to include other individuals, and the general public.
+The timing and manner of disclosure is governed by the
+[Eclipse Security Policy](https://www.eclipse.org/security/policy.php).
+
+Publicly disclosed issues are listed on the
+[Disclosed Vulnerabilities Page](https://www.eclipse.org/security/known.php).