CVE-2013-1821

lib/rexml/text.rb en el analizador REXML en Ruby anterior a 1.9.3-p392, permite a atacantes remotos provocar una denegación de servicio (consumo de memoria o caída de la aplicación) a través de nodos de texto manipulados en un documento XML. Aka como ataque XML Entity Expansion (XEE).

The safe-level feature in Ruby 1.8.7 allows context-dependent attackers to modify strings via the NameError#to_s method when operating on Ruby objects. NOTE: this issue is due to an incomplete fix for CVE-2011-1005. lib/rexml/text.rb in the REXML parser in Ruby before 1.9.3-p392 allows remote attackers to cause a denial of service (memory consumption and crash) via crafted text nodes in an XML document, aka an XML Entity Expansion attack. A flaw was found in Ruby's SSL client's hostname identity check when handling certificates that contain hostnames with NULL bytes. An attacker could potentially exploit this flaw to conduct man-in-the-middle attacks to spoof SSL servers. Note that to exploit this issue, an attacker would need to obtain a carefully-crafted certificate signed by an authority that the client trusts. The updated packages have been patched to correct these issues.