Buffer overflow in pattern.c in libxslt before 1.1.24 allows context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via an XSL style sheet file with a long XSLT "transformation match" condition that triggers a large number of steps.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.