Cyrus SASL 2.1.23, 2.1.26, and earlier does not properly handle when a NULL value is returned upon an error by the crypt function as implemented in glibc 2.17 and later, which allows remote attackers to cause a denial of service (thread crash and consumption) via (1) an invalid salt or, when FIPS-140 is enabled, a (2) DES or (3) MD5 encrypted password, which triggers a NULL pointer dereference.

Multiple buffer overflows in the CMU Cyrus SASL library before 2.1.23 might allow remote attackers to execute arbitrary code or cause a denial of service (application crash) via strings that are used as input to the sasl_encode64 function in lib/saslutil.c.

The (1) libsasl and (2) libsasl2 libraries in Cyrus-SASL 2.1.18 and earlier trust the SASL_PATH environment variable to find all available SASL plug-ins, which allows local users to execute arbitrary code by modifying the SASL_PATH to point to malicious programs.

Buffer overflow in digestmd5.c CVS release 1.170 (also referred to as digestmda5.c), as used in the DIGEST-MD5 SASL plugin for Cyrus-SASL but not in any official releases, allows remote attackers to execute arbitrary code.