Zulip Server 5.6 and Zulip Mobile v27.190 security releases

[Tim Abbott]

We've just released Zulip Server 5.6. This is a security release, fixing an important security issue (CVE-2022-36048).

We've also released Zulip Mobile v27.190, which fixes a related security issue (CVE-2022-35962) in the Zulip mobile apps.

See the blog post for the details.

-Tim Abbott, for the Zulip team