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The sqlite3-ruby gem in the rubygem-sqlite3 package before 1.2.4-0.5.1 in SUSE Linux Enterprise (SLE) 11 SP1 uses weak permissions for unspecified files, which allows local users to gain privileges via unknown vectors.
The extractfiles function in installer.rb in RubyGems before 0.9.1 does not check whether files exist before overwriting them, which allows user-assisted remote attackers to overwrite arbitrary files, cause a denial of service, or execute arbitrary code via crafted GEM packages.