-----BEGIN PGP SIGNED MESSAGE-----
AUSCERT External Security Bulletin Redistribution
Multiple OpenSSL vulnerabilities
15 June 2015
AusCERT Security Bulletin Summary
Operating System: FreeBSD
Impact/Access: Access Privileged Data -- Remote/Unauthenticated
Denial of Service -- Remote/Unauthenticated
Provide Misleading Information -- Remote/Unauthenticated
CVE Names: CVE-2015-4000 CVE-2015-1792 CVE-2015-1791
CVE-2015-1790 CVE-2015-1789 CVE-2015-1788
- --------------------------BEGIN INCLUDED TEXT--------------------
- -----BEGIN PGP SIGNED MESSAGE-----
FreeBSD-SA-15:10.openssl Security Advisory
The FreeBSD Project
Topic: Multiple OpenSSL vulnerabilities
Affects: All supported versions of FreeBSD.
Corrected: 2015-06-11 19:07:45 UTC (stable/10, 10.1-STABLE)
2015-06-12 07:23:55 UTC (releng/10.1, 10.1-RELEASE-p12)
2015-06-11 19:39:27 UTC (stable/9, 9.3-STABLE)
2015-06-12 07:23:55 UTC (releng/9.3, 9.3-RELEASE-p16)
2015-06-11 19:39:27 UTC (stable/8, 8.4-STABLE)
2015-06-12 07:23:55 UTC (releng/8.4, 8.4-RELEASE-p30)
CVE Name: CVE-2015-1788, CVE-2015-1789, CVE-2015-1790, CVE-2015-1791
For general information regarding FreeBSD Security Advisories,
including descriptions of the fields above, security branches, and the
following sections, please visit <URL:https://security.FreeBSD.org/>.
FreeBSD includes software from the OpenSSL Project. The OpenSSL Project is
a collaborative effort to develop a robust, commercial-grade, full-featured
Open Source toolkit implementing the Secure Sockets Layer (SSL v2/v3)
and Transport Layer Security (TLS v1) protocols as well as a full-strength
general purpose cryptography library.
II. Problem Description
A vulnerability in the TLS protocol would allow 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 also 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. [CVE-2015-1788]
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. [CVE-2015-1789]
The PKCS#7 parsing code does not handle missing inner EncryptedContent
When verifying a signedData message the CMS code can enter an infinite
loop if presented with an unknown hash function OID. [CVE-2015-1792]
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]
The OpenSSL advisory also describes a problem that is identified as
CVE-2014-8176, which is already fixed by an earlier FreeBSD Errata
A man-in-the-middle attacker may be able to downgrade vulnerable TLS
connections using ephemeral Diffie-Hellman key exchange to 512-bit
export-grade cryptography. [CVE-2015-4000]. On FreeBSD 10.1, the
patch contains a countermeasure for clients by rejecting handshakes
with DH parameters shorter than 768 bits.
An attacker who is able to use a certificate to authenticate with
a remote system perform denial of service against any system which
processes public keys, certificate requests or certificates.
[CVE-2015-1788]. This affects FreeBSD 10.1 only, as the problem
was no longer exist in OpenSSL 0.9.8 series since July 2012.
An attacker can use the CVE-2015-1789 issue by using specifically
crafted certificates and CRLs of various sizes and potentially
cause a segmentation fault, resulting in a DoS on applications that
verify certificates or CRLs.
An attacker who can create specifically crafted malformed ASN.1-encoded
PKCS#7 blobs with missing content and trigger a NULL pointer dereference
on parsing. [CVE-2015-1790]. Applications that decrypt PKCS#7 data
or otherwise parse PKCS#7 structures from untrusted sources are
affected. OpenSSL clients and servers are not affected.
An attacker can perform denial of service against any system which
verifies signedData messages using the CMS code. [CVE-2015-1792]
An attacker may be able to crash multi-thread applications that
supports resumed TLS handshakes. [CVE-2015-1791]
No workaround is available.
Perform one of the following:
1) Upgrade your vulnerable system to a supported FreeBSD stable or
release / security branch (releng) dated after the correction date.
2) To update your vulnerable system via a binary patch:
Systems running a RELEASE version of FreeBSD on the i386 or amd64
platforms can be updated via the freebsd-update(8) utility:
# freebsd-update fetch
# freebsd-update install
3) To update your vulnerable system via a source code patch:
The following patches have been verified to apply to the applicable
FreeBSD release branches.
a) Download the relevant patch from the location below, and verify the
detached PGP signature using your PGP utility.
# fetch https://security.FreeBSD.org/patches/SA-15:10/openssl-10.1.patch
# fetch https://security.FreeBSD.org/patches/SA-15:10/openssl-10.1.patch.asc
# gpg --verify openssl-10.1.patch.asc
[FreeBSD 9.3 and 8.4]
# fetch https://security.FreeBSD.org/patches/SA-15:10/openssl-8.4.patch
# fetch https://security.FreeBSD.org/patches/SA-15:10/openssl-8.4.patch.asc
# gpg --verify openssl-8.4.patch.asc
b) Apply the patch. Execute the following commands as root:
# cd /usr/src
# patch < /path/to/patch
c) Recompile the operating system using buildworld and installworld as
described in <URL:https://www.FreeBSD.org/handbook/makeworld.html>.
Restart all deamons using the library, or reboot the system.
VI. Correction details
The following list contains the correction revision numbers for each
- - -------------------------------------------------------------------------
- - -------------------------------------------------------------------------
To see which files were modified by a particular revision, run the
following command, replacing NNNNNN with the revision number, on a
machine with Subversion installed:
# svn diff -cNNNNNN --summarize svn://svn.freebsd.org/base
Or visit the following URL, replacing NNNNNN with the revision number:
The latest revision of this advisory is available at
- -----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.1.4 (FreeBSD)
- -----END PGP SIGNATURE-----
- --------------------------END INCLUDED TEXT--------------------
You have received this e-mail bulletin as a result of your organisation's
registration with AusCERT. The mailing list you are subscribed to is
maintained within your organisation, so if you do not wish to continue
receiving these bulletins you should contact your local IT manager. If
you do not know who that is, please send an email to email@example.com
and we will forward your request to the appropriate person.
NOTE: Third Party Rights
This security bulletin is provided as a service to AusCERT's members. As
AusCERT did not write the document quoted above, AusCERT has had no control
over its content. The decision to follow or act on information or advice
contained in this security bulletin is the responsibility of each user or
organisation, and should be considered in accordance with your organisation's
site policies and procedures. AusCERT takes no responsibility for consequences
which may arise from following or acting on information or advice contained in
this security bulletin.
NOTE: This is only the original release of the security bulletin. It may
not be updated when updates to the original are made. If downloading at
a later date, it is recommended that the bulletin is retrieved directly
from the author's website to ensure that the information is still current.
Contact information for the authors of the original document is included
in the Security Bulletin above. If you have any questions or need further
information, please contact them directly.
Previous advisories and external security bulletins can be retrieved from:
Australian Computer Emergency Response Team
The University of Queensland
Internet Email: firstname.lastname@example.org
Facsimile: (07) 3365 7031
Telephone: (07) 3365 4417 (International: +61 7 3365 4417)
AusCERT personnel answer during Queensland business hours
which are GMT+10:00 (AEST).
On call after hours for member emergencies only.
-----BEGIN PGP SIGNATURE-----
-----END PGP SIGNATURE-----