The xmlreader in libxml allows remote attackers to cause a denial of service (memory consumption) via crafted XML data, related to an XML Entity Expansion (XEE) attack.
parser.c in libxml2 before 2.9.2 does not properly prevent entity expansion even when entity substitution has been disabled, which allows context-dependent attackers to cause a denial of service (CPU consumption) via a crafted XML document containing a large number of nested entity references, a variant of the "billion laughs" attack.
libxml2 through 2.9.1 does not properly handle external entities expansion unless an application developer uses the xmlSAX2ResolveEntity or xmlSetExternalEntityLoader function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue. NOTE: it could be argued that because libxml2 already provides the ability to disable external entity expansion, the responsibility for resolving this issue lies with application developers; according to this argument, this entry should be REJECTed and each affected application would need its own CVE.
xslt.c in libxslt before 1.1.25 allows context-dependent attackers to cause a denial of service (crash) via a stylesheet that embeds a DTD, which causes a structure to be accessed as a different type. NOTE: this issue is due to an incomplete fix for CVE-2012-2825.
parser.c in libxml2 before 2.9.0, as used in Google Chrome before 28.0.1500.71 and other products, allows remote attackers to cause a denial of service (out-of-bounds read) via a document that ends abruptly, related to the lack of certain checks for the XML_PARSER_EOF state.
libxml2 2.9.0 and earlier allows context-dependent attackers to cause a denial of service (CPU and memory consumption) via an XML file containing an entity declaration with long replacement text and many references to this entity, aka "internal entity expansion" with linear complexity.
Multiple use-after-free vulnerabilities in libxml2 2.9.0 and possibly other versions might allow context-dependent attackers to cause a denial of service (crash) and possibly execute arbitrary code via vectors related to the (1) htmlParseChunk and (2) xmldecl_done functions, as demonstrated by a buffer overflow in the xmlBufGetInputBase function.
libxslt before 1.1.28 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) via an (1) empty match attribute in a XSL key to the xsltAddKey function in keys.c or (2) uninitialized variable to the xsltDocumentFunction function in functions.c.
libxml2 before 2.8.0 computes hash values without restricting the ability to trigger hash collisions predictably, which allows context-dependent attackers to cause a denial of service (CPU consumption) via crafted XML data.
Heap-based buffer underflow in the xmlParseAttValueComplex function in parser.c in libxml2 2.9.0 and earlier, as used in Google Chrome before 23.0.1271.91 and other products, allows remote attackers to cause a denial of service or possibly execute arbitrary code via crafted entities in an XML document.