From secunia security advisory at $URL:
Two vulnerabilities with unknown impacts have been reported in Oracle MySQL Server.
The vulnerabilities are caused due to unspecified errors. No further information is currently available.
The vulnerabilities are reported in versions prior to 5.5.22.
Update to version 5.5.22.
The advisory does not mention much, can you check if our version is affected or not?
CVE assignment and more info in http://www.openwall.com/lists/oss-security/2012/04/13/7.
MySQL 5.1.x before 5.1.62 and 5.5.x before 5.5.22 allows remote
authenticated users to cause a denial of service (assertion failure and
mysqld abort) by deleting a record and using HANDLER READ NEXT.
This issue was resolved and addressed in
GLSA 201308-06 at http://security.gentoo.org/glsa/glsa-201308-06.xml
by GLSA coordinator Sergey Popov (pinkbyte).