Nokogiri gem, via libxslt, is affected by multiple vulnerabilities

Nokogiri v1.10.5 has been released.

This is a security release. It addresses three CVEs in upstream libxml2,
for which details are below.

If you’re using your distro’s system libraries, rather than Nokogiri’s
vendored libraries, there’s no security need to upgrade at this time,
though you may want to check with your distro whether they’ve patched this
(Canonical has patched Ubuntu packages). Note that libxslt 1.1.34 addresses
these vulnerabilities.

Full details about the security update are available in Github Issue
[#1943] https://github.com/sparklemotion/nokogiri/issues/1943.

CVE-2019-13117

https://people.canonical.com/~ubuntu-security/cve/2019/CVE-2019-13117.html

Priority: Low

Description: In numbers.c in libxslt 1.1.33, an xsl:number with certain format strings
could lead to a uninitialized read in xsltNumberFormatInsertNumbers. This
could allow an attacker to discern whether a byte on the stack contains the
characters A, a, I, i, or 0, or any other character.

Patched with commit https://gitlab.gnome.org/GNOME/libxslt/commit/c5eb6cf3aba0af048596106ed839b4ae17ecbcb1

CVE-2019-13118

https://people.canonical.com/~ubuntu-security/cve/2019/CVE-2019-13118.html

Priority: Low

Description: In numbers.c in libxslt 1.1.33, a type holding grouping characters of an
xsl:number instruction was too narrow and an invalid character/length
combination could be passed to xsltNumberFormatDecimal, leading to a read
of uninitialized stack data

Patched with commit https://gitlab.gnome.org/GNOME/libxslt/commit/6ce8de69330783977dd14f6569419489875fb71b

CVE-2019-18197

https://people.canonical.com/~ubuntu-security/cve/2019/CVE-2019-18197.html

Priority: Medium

Description: In xsltCopyText in transform.c in libxslt 1.1.33, a pointer variable isn’t
reset under certain circumstances. If the relevant memory area happened to
be freed and reused in a certain way, a bounds check could fail and memory
outside a buffer could be written to, or uninitialized data could be
disclosed.

Patched with commit https://gitlab.gnome.org/GNOME/libxslt/commit/2232473733b7313d67de8836ea3b29eec6e8e285