Bug 390371 (CVE-2007-5502)

Summary: CVE-2007-5502 openssl FIPS module PRNG flaw
Product: [Other] Security Response Reporter: Tomas Hoger <thoger>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: security-response-team, tmraz
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: Bug Fix
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Last Closed: 2007-11-30 10:13:52 UTC Type: ---
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description Tomas Hoger 2007-11-19 13:58:07 UTC
From OpenSSL advisory:

A significant flaw in the PRNG implementation for the OpenSSL FIPS Object 
Module v1.1.1 (certificate #733, 
http://csrc.nist.gov/groups/STM/cmvp/documents/140-1/140val-all.htm#733) 
has been reported by Geoff Lowe of Secure Computing corporation. Due to a 
coding error in the FIPS self-test the auto-seeding never takes place. 
That means that the PRNG key and seed used correspond to the last 
self-test. The FIPS PRNG gets additional seed data only from date-time 
information, so the generated random data is far more predictable than it 
should be, especially for the first few calls (CVE-2007-5502).

Note that this PRNG bug is only present in the v1.1.1 implementation and 
not in the regular OpenSSL product or in the OpenSSL FIPS Object Module 
v1.2 now undergoing validation testing. Only those applications using 
v1.1.1 of the OpenSSL FIPS Object Module which enter FIPS mode are 
affected. Applications which do not enter FIPS mode or which use any other 
version of OpenSSL are not affected.

Bugs like this in open source software are routinely found and corrected 
with a patch and/or updated source distribution. In this case two 
different such fixes have been developed by Dr Stephen Henson 
<steve-at-openssl.org>: http://www.openssl.org/news/patch-CVE-2007-5502-1.txt 
(the simplest direct fix) and: 
http://www.openssl.org/news/patch-CVE-2007-5502-2.txt (a workaround which 
avoids touching the PRNG code directly). However, for FIPS 140-2 validated 
software no changes are permitted without prior CMVP approval.

In consultation with the CMT test lab we will be submitting a "letter 
change" update request to the CMVP for the latter of these two patches. 
This latter patch also addresses a minor issue with the continuous PRNG 
self test. Once (and if) approved the new distribution containing this 
patch will be posted to replace the current distribution at 
http://openssl.org/source/openssl-fips-1.1.1.tar.gz.

Comment 1 Tomas Mraz 2007-11-19 14:24:19 UTC
If it really affects only FIPS certified versions of OpenSSL then we are not
vulnerable at all. We do not ship certified version of OpenSSL.


Comment 3 Mark J. Cox 2007-11-30 10:13:09 UTC
now public, removing embargo
http://www.openssl.org/news/secadv_20071129.txt