// Module included in the following assemblies:
//
// security/nbde-implementation-guide.adoc

:_mod-docs-content-type: PROCEDURE
[id="nbde-compromise-of-key-material_{context}"]
= Rekeying compromised key material

If key material is potentially exposed to unauthorized third parties, such as through the physical theft of a Tang server or associated data, immediately rotate the keys.

.Procedure

. Rekey any Tang server holding the affected material.
. Rekey all clients using the Tang server.
. Destroy the original key material.
. Scrutinize any incidents that result in unintended exposure of the master encryption key. If possible, take compromised nodes offline and re-encrypt their disks.

[TIP]
Reformatting and reinstalling on the same physical hardware, although slow, is easy to automate and test.
