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CVE-2025-55780 is a null pointer dereference vulnerability in Artifex MuPDF affecting EPUB rendering. The flaw occurs in break_word_for_overflow_wrap() when processing a malformed EPUB document. In the vulnerable code path, the function invokes fz_html_split_flow() to split a FLOW_WORD node and subsequently accesses node->next->overflow_wrap without verifying that node->next is valid. If the split operation fails or produces only a partial node chain, the invalid dereference can crash the application. Reported vulnerable versions include MuPDF 1.26.4, and NVD analysis indicates affected versions from 1.24.0 up to, but excluding, 1.26.7.
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No valid public exploits. Mallory filtered out 1 candidate as fakes, detection scripts, or README-only repos.
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Null pointer dereference in MuPDF’s EPUB rendering path (break_word_for_overflow_wrap / fz_html_split_flow) that can crash the application when processing a malformed EPUB document (denial of service).
An unpatched vulnerability tracked as CVE-2025-55780 affecting Debian and Ubuntu Linux distributions and the MuPDF package, with a CVSS v3.0 vector indicating network-reachable availability impact.
A null pointer dereference vulnerability in MuPDF 1.26.4 related to an EPUB rendering function, scored 7.5 (CVSSv3) in the provided content.
Null pointer dereference in MuPDF’s EPUB rendering path (break_word_for_overflow_wrap / fz_html_split_flow) that can be triggered by a malformed EPUB, leading to an application crash (denial of service).
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Cross-references every affected SKU, including bundled OEM variants.
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