Lemur subject to insecure random generation

Overview

Lemur was using insecure random generation for its example configuration file, as well as for some utilities.

Impact

The potentially affected generated items include:

Configuration item	Config option name (if applicable)	Documentation link (if applicable)	Rotation option	Code reference(s)
Flask session secret	SECRET_KEY	Flask documentation	Generate a new secret and place in config; all existing sessions will be invalidated	N/A, internal to Flask
Lemur token secret	LEMUR_TOKEN_SECRET	Lemur's configuration documentation	Generate a new secret and place in config; all existing JWTs will be invalidated and must be regenerated (including API keys)	1, 2
Lemur database encryption key	LEMUR_ENCRYPTION_KEYS	Lemur's configuration documentation	A new key can be generated and added to this list, but existing data encrypted with prior keys cannot be re-encrypted unless you write a custom re-encryption process	1
OAuth2 state token secret key	OAUTH_STATE_TOKEN_SECRET	Lemur's configuration documentation	Generate a new secret and place in config	1
Randomly generated passphrases for openssl keystores	N/A, generated at runtime but persisted	N/A	Re-export all openssl keystores and replace them wherever they're in use	1
Initial password for LDAP users	N/A, generated at runtime but persisted	N/A	N/A, cannot be rotated*	1
Initial password for Ping/OAuth2 users	N/A, generated at runtime but persisted	N/A	N/A, cannot be rotated*	1
Oauth2 nonce	N/A, short-lived runtime secret	N/A	N/A, rotation is not required (these are short-lived)	1
Verisign certificate enrollment challenges	N/A, short-lived runtime secret	N/A	N/A, rotation is not required (these are short-lived)	1

If your deployment of Lemur is using any of the above config secrets that were generated by Lemur's example config (i.e., generated using insecure randomness), you should rotate those config secrets. If you generated your config secrets in a more secure way, they are not known to be compromised, but you should still upgrade Lemur to ensure that you receive code fixes for the runtime-generated secrets.

For general information and guidance on Lemur secret configuration, see Lemur's configuration documentation, which includes information on many of the configuration options listed above.

*For the user passwords: Even though these users are configured to use SSO, they do get generated with valid database passwords that can be used to log in. Since Lemur doesn't have an option to change passwords (#3888), one option for rotating them would be to directly modify the value in the database to some other unguessable string (you do not need to know the plaintext password since it won't be used).

Patches

The patch is available in v1.3.2.

Workarounds

No workarounds are available.

References

N/A