Debian LTS Advisory ([SECURITY] [DLA 1008-1] libxml2 security update)

CVE-2017-7375 Missing validation for external entities in xmlParsePEReference CVE-2017-9047 CVE-2017-9048 A buffer overflow was discovered in libxml2 20904-GITv2.9.4-16-g0741801. The function xmlSnprintfElementContent in valid.c is supposed to recursively dump the element content definition into a char buffer 'buf' of size 'size'. The variable len is assigned strlen(buf). If the content->type is XML_ELEMENT_CONTENT_ELEMENT, then (i) the content->prefix is appended to buf (if it actually fits) whereupon (ii) content->name is written to the buffer. However, the check for whether the content->name actually fits also uses 'len' rather than the updated buffer length strlen(buf). This allows us to write about 'size' many bytes beyond the allocated memory. This vulnerability causes programs that use libxml2, such as PHP, to crash. CVE-2017-9049 CVE-2017-9050 libxml2 20904-GITv2.9.4-16-g0741801 is vulnerable to a heap-based buffer over-read in the xmlDictComputeFastKey function in dict.c. This vulnerability causes programs that use libxml2, such as PHP, to crash. This vulnerability exists because of an incomplete fix for libxml2 Bug 759398.

libxml2 on Debian Linux

This check tests the installed software version using the apt package manager.

For Debian 7 'Wheezy', these problems have been fixed in version 2.8.0+dfsg1-7+wheezy8. We recommend that you upgrade your libxml2 packages.