The glibc packages contain the standard C libraries used by multipleprograms on the system. These packages contain the standard C and thestandard math libraries. Without these two libraries, a Linux system cannotfunction properly.An integer overflow flaw, leading to a heap-based buffer overflow, wasfound in the way the glibc library read timezone files. If acarefully-crafted timezone file was loaded by an application linked againstglibc, it could cause the application to crash or, potentially, executearbitrary code with the privileges of the user running the application.(CVE-2009-5029)A denial of service flaw was found in the remote procedure call (RPC)implementation in glibc. A remote attacker able to open a large number ofconnections to an RPC service that is using the RPC implementation fromglibc, could use this flaw to make that service use an excessive amount ofCPU time. (CVE-2011-4609)This update also fixes the following bugs:Users should upgrade to these updated packages, which contain backportedpatches to resolve these issues.