CVE-2018-9251

The xz_decomp function in xzlib.c in libxml2 2.9.8, if --with-lzma is used, allows remote attackers to cause a denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint, a different vulnerability than CVE-2015-8035.

A flaw was found in libxml2 2.9.8. The xz_decomp function in xzlib.c, if --with-lzma is used, allows remote attackers to cause a denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint (CVE-2018-9251, CVE-2018-14567).

A null pointer dereference vulnerability exists in the xpath.c:xmlXPathCompOpEval() function of libxml2 when parsing invalid XPath expression. Applications processing untrusted XSL format inputs with the use of libxml2 library may be vulnerable to denial of service attack due to crash of the application (CVE-2018-14404).

The libxml2 package has been updated to version 2.9.9 to fix these issues and other bugs.

The perl-XML-LibXML package has been rebuilt against the updated libxml2.

These are all security issues fixed in the libxml2-2-2.9.12-1.2 package on the GA media of openSUSE Tumbleweed.

This update for libxml2 fixes the following security issues:

• CVE-2018-9251: The xz_decomp function allowed remote attackers to cause a denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint (bsc#1088279)
• CVE-2018-14567: Prevent denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint (bsc#1105166)
• CVE-2018-14404: Prevent NULL pointer dereference in the xmlXPathCompOpEval() function when parsing an invalid XPath expression in the XPATH_OP_AND or XPATH_OP_OR case leading to a denial of service attack (bsc#1102046)

This update for libxml2 fixes the following security issues:

• CVE-2018-9251: The xz_decomp function allowed remote attackers to cause a denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint (bsc#1088279).
• CVE-2018-14567: Prevent denial of service (infinite loop) via a crafted XML file that triggers LZMA_MEMLIMIT_ERROR, as demonstrated by xmllint (bsc#1105166).
• CVE-2018-14404: Prevent NULL pointer dereference in the xmlXPathCompOpEval() function when parsing an invalid XPath expression in the XPATH_OP_AND or XPATH_OP_OR case leading to a denial of service attack (bsc#1102046).
• CVE-2017-18258: The xz_head function allowed remote attackers to cause a denial of service (memory consumption) via a crafted LZMA file, because the decoder functionality did not restrict memory usage to what is required for a legitimate file (bsc#1088601).