CVE-2015-6908

The ber_get_next function in libraries/liblber/io.c in OpenLDAP 2.4.42 and earlier allows remote attackers to cause a denial of service (reachable assertion and application crash) via crafted BER data, as demonstrated by an attack against slapd.

By sending a crafted packet, an attacker can cause the OpenLDAP daemon to crash with a SIGABRT. This is due to an assert() call in the ber_get_next() method in a/libraries/liblber/io.c that is hit when decoding tampered BER data (CVE-2015-6908)

These are all security issues fixed in the libldap-2_4-2-2.4.44-22.1 package on the GA media of openSUSE Tumbleweed.

This update fixes the following security issue:

• CVE-2015-6908. Passing a crafted packet to the function ber_get_next(), an attacker may cause a remote denial of service, crashing the OpenLDAP server (bsc#945582).

This update fixes the following security issues:

• CVE-2015-6908: The ber_get_next function allowed remote attackers to cause a denial of service (reachable assertion and application crash) via crafted BER data, as demonstrated by an attack against slapd. (bsc#945582)
• CVE-2015-4000: Fix weak Diffie-Hellman size vulnerability. (bsc#937766)

It also fixes the following non-security bugs:

• bsc#955210: Unresponsive LDAP host lookups in IPv6 environment

This update adds the following functionality:

• fate#319300: SHA2 password hashing module that can be loaded on-demand.

This update fixes the following security issues:

• CVE-2015-6908: The ber_get_next function allowed remote attackers to cause a denial of service (reachable assertion and application crash) via crafted BER data, as demonstrated by an attack against slapd. (bsc#945582)
• CVE-2015-4000: Fix weak Diffie-Hellman size vulnerability. (bsc#937766)

This rebuild for sles11sp4-docker-image fixes several important security issues done in libraries contained inside, for glibc, openssl, curl and openldap2.

glibc security fixes:

• CVE-2015-7547: A stack-based buffer overflow in getaddrinfo allowed remote attackers to cause a crash or execute arbitrary code via crafted and timed DNS responses (bsc#961721)
• CVE-2015-8777: Insufficient checking of LD_POINTER_GUARD environment variable allowed local attackers to bypass the pointer guarding protection of the dynamic loader on set-user-ID and set-group-ID programs (bsc#950944)
• CVE-2015-8776: Out-of-range time values passed to the strftime function may cause it to crash, leading to a denial of service, or potentially disclosure information (bsc#962736)
• CVE-2015-8778: Integer overflow in hcreate and hcreate_r could have caused an out-of-bound memory access. leading to application crashes or, potentially, arbitrary code execution (bsc#962737)
• CVE-2014-9761: A stack overflow (unbounded alloca) could have caused applications which process long strings with the nan function to crash or, potentially, execute arbitrary code. (bsc#962738)
• CVE-2015-8779: A stack overflow (unbounded alloca) in the catopen function could have caused applications which pass long strings to the catopen function to crash or, potentially execute arbitrary code. (bsc#962739)

glibc non-security bugfixes:

• bsc#930721: Accept leading and trailing spaces in getdate input string
• bsc#942317: Recognize power8 platform
• bsc#950944: Always enable pointer guard
• bsc#956988: Fix deadlock in __dl_iterate_phdr

openssl 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-2016-0705 (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-2016-0799 (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.

-…

The ber_get_next function in libraries/liblber/io.c in OpenLDAP 2.4.42 and earlier allows remote attackers to cause a denial of service (reachable assertion and application crash) via crafted BER data, as demonstrated by an attack against slapd.

Denis Andzakovic discovered that OpenLDAP incorrectly handled certain BER data. A remote attacker could possibly use this issue to cause OpenLDAP to crash, resulting in a denial of service. (CVE-2015-6908)

Dietrich Clauss discovered that the OpenLDAP package incorrectly shipped with a potentially unsafe default access control configuration. Depending on how the database is configure, this may allow users to impersonate others by modifying attributes such as their Unix user and group numbers. (CVE-2014-9713)