cairo 1.16.0 in cairo_ft_apply_variations() in cairo-ft-font.c would free memory using a free function incompatible with WebKit's fastMalloc leading to an application crash with a "free(): invalid pointer" error.

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DEBIAN-CVE-2018-19876

cairo 1.16.0, in cairoftapplyvariations in cairo-ft-font.c, would free memory using a free function incompatible with WebKit's fastMalloc, leading to an application crash with a "free: invalid pointer" error...