SystemTap 1.0, when the --unprivileged option is used, does not properly restrict certain data sizes, which allows local users to (1) cause a denial of service or gain privileges via a print operation with a large number of arguments that trigger a kernel stack overflow, (2) cause a denial of service via crafted DWARF expressions that trigger a kernel stack frame overflow, or (3) cause a denial of service (infinite loop) via vectors that trigger creation of large unwind tables, related to Common Information Entry (CIE) and Call Frame Instruction (CFI) records.
https://www.redhat.com/archives/fedora-package-announce/2009-October/msg00793.html
https://www.redhat.com/archives/fedora-package-announce/2009-October/msg00627.html
https://bugzilla.redhat.com/show_bug.cgi?id=529175
http://www.vupen.com/english/advisories/2009/2989
http://www.securityfocus.com/bid/36778
http://www.openwall.com/lists/oss-security/2009/10/21/1