GLSA

GLSA stands for Gentoo Linux Security Advisory, an XML document detailing a security flaw in an application. glsa-check, as well as other non-official programs apply these patches to affected systems.

Links

 * The GLSA homepage
 * GLEP 14 (The one that started it all)
 * Getting GLSA's specific to your setup by email
 * The Gentoo Security RDF feed