Security update for openssl

SUSE Security Update: Security update for openssl
Announcement ID: SUSE-SU-2016:0621-1
Rating: important
References: #952871 #963415 #968046 #968047 #968048 #968050 #968051 #968053 #968265 #968374
Affected Products:
  • SUSE Linux Enterprise Server 11-SECURITY

  • An update that solves 9 vulnerabilities and has one errata is now available.

    Description:


    This update for openssl fixes various security issues and bugs:

    Security issues fixed:
    - CVE-2016-0800 aka the "DROWN" attack (bsc#968046): OpenSSL was
    vulnerable to a cross-protocol attack that could lead to decryption of
    TLS sessions by using a server supporting SSLv2 and EXPORT cipher suites
    as a Bleichenbacher RSA padding oracle.

    This update changes the openssl library to:

    * Disable SSLv2 protocol support by default.

    This can be overridden by setting the environment variable
    "OPENSSL_ALLOW_SSL2" or by using SSL_CTX_clear_options using the
    SSL_OP_NO_SSLv2 flag.

    Note that various services and clients had already disabled SSL
    protocol 2 by default previously.

    * Disable all weak EXPORT ciphers by default. These can be reenabled if
    required by old legacy software using the environment variable
    "OPENSSL_ALLOW_EXPORT".

    - CVE-2016-0702 aka the "CacheBleed" attack. (bsc#968050) Various changes
    in the modular exponentation code were added that make sure that it is
    not possible to recover RSA secret keys by analyzing cache-bank
    conflicts on the Intel Sandy-Bridge microarchitecture.

    Note that this was only exploitable if the malicious code was running
    on the same hyper threaded Intel Sandy Bridge processor as the victim
    thread performing decryptions.

    - CVE-2016-0705 (bnc#968047): A double free() bug in the DSA ASN1 parser
    code was fixed that could be abused to facilitate a denial-of-service
    attack.

    - CVE-2016-0797 (bnc#968048): The BN_hex2bn() and BN_dec2bn() functions
    had a bug that could result in an attempt to de-reference a NULL pointer
    leading to crashes. This could have security consequences if these
    functions were ever called by user applications with large untrusted
    hex/decimal data. Also, internal usage of these functions in OpenSSL
    uses data from config files
    or application command line arguments. If user developed applications
    generated config file data based on untrusted data, then this could
    have had security consequences as well.

    - CVE-2016-0798 (bnc#968265) The SRP user database lookup method
    SRP_VBASE_get_by_user() had a memory leak that attackers could abuse to
    facility DoS attacks. To mitigate the issue, the seed handling in
    SRP_VBASE_get_by_user() was disabled even if the user has configured a
    seed. Applications are advised to migrate to SRP_VBASE_get1_by_user().

    - CVE-2016-0799 (bnc#968374) On many 64 bit systems, the internal fmtstr()
    and doapr_outch() functions could miscalculate the length of a string
    and attempt to access out-of-bounds memory locations. These problems
    could have enabled attacks where large amounts of untrusted data is
    passed to the BIO_*printf functions. If applications use these functions
    in this way then they could have been vulnerable. OpenSSL itself uses
    these functions when printing out human-readable dumps of ASN.1 data.
    Therefore applications that print this data could have been vulnerable
    if the data is from untrusted sources. OpenSSL command line applications
    could also have been vulnerable when they print out ASN.1 data, or if
    untrusted data is passed as command line arguments. Libssl is not
    considered directly vulnerable.

    - CVE-2015-3197 (bsc#963415): The SSLv2 protocol did not block disabled
    ciphers.

    Note that the March 1st 2016 release also references following CVEs that
    were fixed by us with CVE-2015-0293 in 2015:

    - CVE-2016-0703 (bsc#968051): This issue only affected versions of OpenSSL
    prior to March 19th 2015 at which time the code was refactored to
    address vulnerability CVE-2015-0293. It would have made the above
    "DROWN" attack much easier.
    - CVE-2016-0704 (bsc#968053): "Bleichenbacher oracle in SSLv2" This issue
    only affected versions of OpenSSL prior to March 19th 2015 at which time
    the code was refactored to address vulnerability CVE-2015-0293. It would
    have made the above "DROWN" attack much easier.

    Bugs fixed:
    - Avoid running OPENSSL_config twice. This avoids breaking engine loading.
    (bsc#952871)

    Patch Instructions:

    To install this SUSE Security Update use YaST online_update.
    Alternatively you can run the command listed for your product:

    • SUSE Linux Enterprise Server 11-SECURITY:
      zypper in -t patch secsp3-openssl1-12429=1

    To bring your system up-to-date, use "zypper patch".

    Package List:

    • SUSE Linux Enterprise Server 11-SECURITY (i586 ia64 ppc64 s390x x86_64):
      • libopenssl1-devel-1.0.1g-0.40.1
      • libopenssl1_0_0-1.0.1g-0.40.1
      • openssl1-1.0.1g-0.40.1
      • openssl1-doc-1.0.1g-0.40.1
    • SUSE Linux Enterprise Server 11-SECURITY (ppc64 s390x x86_64):
      • libopenssl1_0_0-32bit-1.0.1g-0.40.1
    • SUSE Linux Enterprise Server 11-SECURITY (ia64):
      • libopenssl1_0_0-x86-1.0.1g-0.40.1

    References: