A memory leak in rsyslog before 5.7.6 was found in the way deamon processed log messages are logged when $RepeatedMsgReduction was enabled. A local attacker could use this flaw to cause a denial of the rsyslogd daemon service by crashing the service via a sequence of repeated log messages sent within short periods of time.
https://security-tracker.debian.org/tracker/CVE-2011-1488
https://github.com/rsyslog/rsyslog/commit/1ef709cc97d54f74d3fdeb83788cc4b01f4c6a2a
https://access.redhat.com/security/cve/cve-2011-1488
http://lists.opensuse.org/opensuse-security-announce/2011-04/msg00005.html