Bug 1202410 (CVE-2015-0285)

Summary: CVE-2015-0285 openssl: handshake with unseeded PRNG
Product: [Other] Security Response Reporter: Martin Prpič <mprpic>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED NOTABUG QA Contact:
Severity: low Docs Contact:
Priority: low    
Version: unspecifiedCC: aavati, acathrow, alonbl, bazulay, bmcclain, cdewolf, cfergeau, dandread, darran.lofthouse, dblechte, dknox, ecohen, erik-fedora, gklein, idith, iheim, jason.greene, jawilson, jboss-set, jclere, jdoyle, ktietz, lfarkas, lgao, lsurette, marcandre.lureau, mehmetgelisin, michal.skrivanek, myarboro, nlevinki, pgier, pslavice, rbalakri, rfortier, rhs-bugs, rh-spice-bugs, rjones, rsvoboda, security-response-team, sgirijan, smohan, ssaha, tmraz, twalsh, vbellur, vtunka, weli, yeylon
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Fixed In Version: openssl 1.0.2a Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2015-03-18 03:38:40 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Bug Depends On:    
Bug Blocks: 1202442    

Description Martin Prpič 2015-03-16 14:48:46 UTC
Under certain conditions an OpenSSL 1.0.2 client can complete a handshake with an unseeded PRNG. The conditions are:

- The client is on a platform where the PRNG has not been seeded automatically, and the user has not seeded manually

- A protocol specific client method version has been used (i.e. not SSL_client_methodv23)

- A ciphersuite is used that does not require additional random data from the PRNG beyond the initial ClientHello client random (e.g. PSK-RC4-SHA).

If the handshake succeeds then the client random that has been used will have
been generated from a PRNG with insufficient entropy and therefore the output
may be predictable.

For example using the following command with an unseeded openssl will succeed on an unpatched platform:

openssl s_client -psk 1a2b3c4d -tls1_2 -cipher PSK-RC4-SHA

This issue affects OpenSSL version 1.0.2, and is fixed in version 1.0.2a.

Upstream patch:



Red Hat would like to thank the OpenSSL project for reporting this issue. Upstream acknowledges Matt Caswell of the OpenSSL development team as the original reporter.

Comment 1 Huzaifa S. Sidhpurwala 2015-03-18 03:37:59 UTC

This issue did not affect the versions of openssl as shipped with Red Hat Enterprise Linux 5, 6, and 7.