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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.43%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.43% probability · 36th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-476
- Affected
- artifex/mupdf
- Source
- cve@mitre.org
References
- https://bugs.ghostscript.com/show_bug.cgi?id=708720Issue Tracking, Third Party Advisory
- https://cgit.ghostscript.com/cgi-bin/cgit.cgi/mupdf.git/commit/?id=bdd5d241748807378a78a622388e0312332513c5Permissions Required
- https://github.com/ISH2YU/CVE-2025-55780/tree/mainThird Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.