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Issue #1858

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CVE-2016-3704: Unsafe use of bash $RANDOM for NSS DB password and seed

Added by rbarlow almost 8 years ago. Updated almost 5 years ago.

Status:
CLOSED - CURRENTRELEASE
Priority:
Normal
Assignee:
Category:
-
Sprint/Milestone:
-
Start date:
Due date:
Estimated time:
Severity:
3. High
Version:
Platform Release:
2.8.5
OS:
Triaged:
Yes
Groomed:
No
Sprint Candidate:
No
Tags:
Pulp 2
Sprint:
Quarter:

Description

In working on another security issue in this same script, I noticed that
Pulp's pulp-qpid-ssl-cfg script uses bash's $RANDOM in unsafe ways. One
of them is already being fixed as part of another CVE (the TMP directory
is unsafe, CVE-2016-3696), but the other two uses are:

0) The default NSS DB password is a single value from $RANDOM,
limiting it to the strings from 0 to 32768:

https://github.com/pulp/pulp/blob/pulp-2.8.2-1/server/bin/pulp-qpid-ssl-cfg#L25

1) The certutil -z flag receives a "noise file". The script uses $RANDOM to
populate a file with numbers to generate this file:

https://github.com/pulp/pulp/blob/pulp-2.8.2-1/server/bin/pulp-qpid-ssl-cfg#L97-L105

Since $RANDOM is used in this way, the seed file ends up having low
diversity since only 11 possible bytes appear in the file: ASCII 0-9 and
newline. Additionally, bash's RANDOM has not been described as a
sound random generator for such purposes.

pwgen can be used to fix #0, but I'm not sure we want to depend
on pwgen. One possibility is to avoid having a default password and force
the user to provide one. Suggestions for this problem welcome.

For #1 we should just grab 8 kB from /dev/urandom and call it a day.

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