Exploit the possiblities

FreeBSD Security Advisory - FreeBSD-SA-16:17.openssl

FreeBSD Security Advisory - FreeBSD-SA-16:17.openssl
Posted May 5, 2016
Authored by OpenSSL Project | Site security.freebsd.org

FreeBSD Security Advisory - The padding check in AES-NI CBC MAC was rewritten to be in constant time by making sure that always the same bytes are read and compared against either the MAC or padding bytes. But it no longer checked that there was enough data to have both the MAC and padding bytes. [CVE-2016-2107] An overflow can occur in the EVP_EncodeUpdate() function which is used for Base64 encoding of binary data. [CVE-2016-2105] An overflow can occur in the EVP_EncryptUpdate() function, however it is believed that there can be no overflows in internal code due to this problem. [CVE-2016-2106] When ASN.1 data is read from a BIO using functions such as d2i_CMS_bio() a short invalid encoding can casuse allocation of large amounts of memory potentially consuming excessive resources or exhausting memory. [CVE-2016-2109] ASN1 Strings that are over 1024 bytes can cause an overread in applications using the X509_NAME_oneline() function on EBCDIC systems. [CVE-2016-2176] FreeBSD does not run on any EBCDIC systems and therefore is not affected. A MITM attacker can use a padding oracle attack to decrypt traffic when the connection uses an AES CBC cipher and the server support AES-NI. [CVE-2016-2107] If an attacker is able to supply very large amounts of input data then a length check can overflow resulting in a heap corruption. [CVE-2016-2105] Any application parsing untrusted data through d2i BIO functions are vulnerable to memory exhaustion attack. [CVE-2016-2109] TLS applications are not affected.

tags | advisory, overflow
systems | freebsd
advisories | CVE-2016-2105, CVE-2016-2106, CVE-2016-2107, CVE-2016-2109
MD5 | 0cd350926d2b0a4e5eb3cc47ba9a5d7d

FreeBSD Security Advisory - FreeBSD-SA-16:17.openssl

Change Mirror Download
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

=============================================================================
FreeBSD-SA-16:17.openssl Security Advisory
The FreeBSD Project

Topic: Multiple OpenSSL vulnerabilities

Category: contrib
Module: openssl
Announced: 2016-05-04
Credits: OpenSSL Project
Affects: All supported versions of FreeBSD.
Corrected: 2016-05-03 18:54:20 UTC (stable/10, 10.3-STABLE)
2016-05-04 15:25:47 UTC (releng/10.3, 10.3-RELEASE-p2)
2016-05-04 15:26:23 UTC (releng/10.2, 10.2-RELEASE-p16)
2016-05-04 15:27:09 UTC (releng/10.1, 10.1-RELEASE-p33)
2016-05-04 06:53:02 UTC (stable/9, 9.3-STABLE)
2016-05-04 15:27:09 UTC (releng/9.3, 9.3-RELEASE-p41)
CVE Name: CVE-2016-2105, CVE-2016-2106, CVE-2016-2107, CVE-2016-2109,
CVE-2016-2176

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/>.

I. Background

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

The padding check in AES-NI CBC MAC was rewritten to be in constant time
by making sure that always the same bytes are read and compared against
either the MAC or padding bytes. But it no longer checked that there was
enough data to have both the MAC and padding bytes. [CVE-2016-2107]

An overflow can occur in the EVP_EncodeUpdate() function which is used for
Base64 encoding of binary data. [CVE-2016-2105]

An overflow can occur in the EVP_EncryptUpdate() function, however it is
believed that there can be no overflows in internal code due to this problem.
[CVE-2016-2106]

When ASN.1 data is read from a BIO using functions such as d2i_CMS_bio()
a short invalid encoding can casuse allocation of large amounts of memory
potentially consuming excessive resources or exhausting memory.
[CVE-2016-2109]

ASN1 Strings that are over 1024 bytes can cause an overread in applications
using the X509_NAME_oneline() function on EBCDIC systems. [CVE-2016-2176]
FreeBSD does not run on any EBCDIC systems and therefore is not affected.

III. Impact

A MITM attacker can use a padding oracle attack to decrypt traffic
when the connection uses an AES CBC cipher and the server support
AES-NI. [CVE-2016-2107]

If an attacker is able to supply very large amounts of input data then a
length check can overflow resulting in a heap corruption. [CVE-2016-2105]

Any application parsing untrusted data through d2i BIO functions are vulnerable
to memory exhaustion attack. [CVE-2016-2109] TLS applications are not affected.

IV. Workaround

No workaround is available.

V. Solution

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.

Restart all daemons that use the library, or reboot the system.

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

Restart all daemons that use the library, or reboot the system.

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.

[FreeBSD 10.x]
# fetch https://security.FreeBSD.org/patches/SA-16:17/openssl-10.patch
# fetch https://security.FreeBSD.org/patches/SA-16:17/openssl-10.patch.asc
# gpg --verify openssl-10.patch.asc

[FreeBSD 9.3]
# fetch https://security.FreeBSD.org/patches/SA-16:17/openssl-9.patc
# fetch https://security.FreeBSD.org/patches/SA-16:17/openssl-9.patch.asc
# gpg --verify openssl-9.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 daemons that use the library, or reboot the system.

VI. Correction details

The following list contains the correction revision numbers for each
affected branch.

Branch/path Revision
- -------------------------------------------------------------------------
stable/9/ r299053
releng/9.3/ r299068
stable/10/ r298999
releng/10.1/ r299068
releng/10.2/ r299067
releng/10.3/ r299066
- -------------------------------------------------------------------------

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:

<URL:https://svnweb.freebsd.org/base?view=revision&revision=NNNNNN>

VII. References

<URL:https://www.openssl.org/news/secadv/20160503.txt>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2105>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2106>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2107>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2109>

<URL:https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-2176>

The latest revision of this advisory is available at
<URL:https://security.FreeBSD.org/advisories/FreeBSD-SA-16:17.openssl.asc>
-----BEGIN PGP SIGNATURE-----
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=PGTh
-----END PGP SIGNATURE-----

Comments

RSS Feed Subscribe to this comment feed

No comments yet, be the first!

Login or Register to post a comment

File Archive:

December 2017

  • Su
  • Mo
  • Tu
  • We
  • Th
  • Fr
  • Sa
  • 1
    Dec 1st
    15 Files
  • 2
    Dec 2nd
    2 Files
  • 3
    Dec 3rd
    1 Files
  • 4
    Dec 4th
    15 Files
  • 5
    Dec 5th
    15 Files
  • 6
    Dec 6th
    18 Files
  • 7
    Dec 7th
    17 Files
  • 8
    Dec 8th
    15 Files
  • 9
    Dec 9th
    13 Files
  • 10
    Dec 10th
    4 Files
  • 11
    Dec 11th
    41 Files
  • 12
    Dec 12th
    42 Files
  • 13
    Dec 13th
    0 Files
  • 14
    Dec 14th
    0 Files
  • 15
    Dec 15th
    0 Files
  • 16
    Dec 16th
    0 Files
  • 17
    Dec 17th
    0 Files
  • 18
    Dec 18th
    0 Files
  • 19
    Dec 19th
    0 Files
  • 20
    Dec 20th
    0 Files
  • 21
    Dec 21st
    0 Files
  • 22
    Dec 22nd
    0 Files
  • 23
    Dec 23rd
    0 Files
  • 24
    Dec 24th
    0 Files
  • 25
    Dec 25th
    0 Files
  • 26
    Dec 26th
    0 Files
  • 27
    Dec 27th
    0 Files
  • 28
    Dec 28th
    0 Files
  • 29
    Dec 29th
    0 Files
  • 30
    Dec 30th
    0 Files
  • 31
    Dec 31st
    0 Files

Top Authors In Last 30 Days

File Tags

Systems

packet storm

© 2016 Packet Storm. All rights reserved.

Services
Security Services
Hosting By
Rokasec
close