A null pointer dereference occurs in the function break_word_for_overflow_wrap() in MuPDF 1.26.4 when rendering a malformed EPUB document. Specifically, the function calls fz_html_split_flow() to split a FLOW_WORD node, but does not check if node->next is valid before accessing node->next->overflow_wrap, resulting in a crash if the split fails or returns a partial node chain.
The product dereferences a pointer that it expects to be valid but is NULL.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Mupdf | Artifex | 1.24.0 (including) | 1.26.7 (excluding) |