CVE-2025-55780: 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…

PriorityP337high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.40%

32.1th percentile

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.

Affected

3 ranges

Vendor	Product	Version range	Fixed in
artifex	mupdf	>= 0 < 1.27.0+ds1-2	1.27.0+ds1-2
artifex	mupdf	>= 1.24.0 < 1.26.7	1.26.7
debian	mupdf	< mupdf 1.27.0+ds1-2 (forky)	mupdf 1.27.0+ds1-2 (forky)

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

osv7.5HIGH

vendor_debian7.5HIGH

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