Advisories ยป MGASA-2015-0246

Updated openssl package fixes security vulnerabilities

Publication date: 19 Jun 2015
Type: security
Affected Mageia releases : 4
CVE: CVE-2015-1788 , CVE-2015-1789 , CVE-2015-1790 , CVE-2015-1791 , CVE-2015-1792 , CVE-2015-4000


A vulnerability in the TLS protocol allows a man-in-the-middle attacker to
downgrade vulnerable TLS connections using ephemeral Diffie-Hellman key
exchange to 512-bit export-grade cryptography. This vulnerability is known
as Logjam (CVE-2015-4000).

When processing an ECParameters structure OpenSSL enters an infinite loop if
the curve specified is over a specially malformed binary polynomial field.
This can be used to perform denial of service against any system which
processes public keys, certificate requests or certificates.  This includes
TLS clients and TLS servers with client authentication enabled

X509_cmp_time does not properly check the length of the ASN1_TIME string and
can read a few bytes out of bounds. In addition, X509_cmp_time accepts an
arbitrary number of fractional seconds in the time string. An attacker can
use this to craft malformed certificates and CRLs of various sizes and
potentially cause a segmentation fault, resulting in a DoS on applications
that verify certificates or CRLs. TLS clients that verify CRLs are affected.
TLS clients and servers with client authentication enabled may be affected
if they use custom verification callbacks (CVE-2015-1789).

The PKCS#7 parsing code does not handle missing inner EncryptedContent
correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs
with missing content and trigger a NULL pointer dereference on parsing

If a NewSessionTicket is received by a multi-threaded client when attempting
to reuse a previous ticket then a race condition can occur potentially
leading to a double free of the ticket data (CVE-2015-1791).

When verifying a signedData message the CMS code can enter an infinite loop
if presented with an unknown hash function OID. This can be used to perform
denial of service against any system which verifies signedData messages
using the CMS code (CVE-2015-1792).