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TI-2025-35178 Aliases CVE-2025-55780GHSA-756h-grq9-2jvh

A null pointer dereference occurs in the function break_word_for_overflow_wrap() in MuPDF…

Priority LOW 33CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-476.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00428 37th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:artifex:mupdf:*:*:*:*:*:*:*:*1.24.0 to before 1.26.7VulnerableArtifex
  • cpe:2.3:a:artifex:mupdf:*:*:*:*:*:*:*:* Versions 1.24.0 to before 1.26.7 Vulnerable ·Artifex

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-55780
  2. 2026-10-03 Alias added: GHSA-756h-grq9-2jvh

References

Advisory 2

Other 1

  • TI-2024-16051 freeglut through 3.4.0 was discovered to contain a memory leak via the menuEntry variable… CVSS 3.1HIGH 7.5
  • TI-2023-27942 A floating point exception (divide-by-zero) vulnerability was discovered in Artifex MuPDF… CVSS 3.1HIGH 7.5
  • TI-2021-02374 Double free in mupdf CVSS 3.1HIGH 7.8
  • TI-2016-07185 Out-of-bounds write in Artifex MuPDF CVSS 3.1HIGH 7.8
  • TI-2012-04514 SumatraPDF 2.1.1/MuPDF 1.0 allows remote attackers to cause an Integer Overflow in the… CVSS 3.1HIGH 7.8
  • TI-2023-27939 A floating point exception (divide-by-zero) vulnerability was discovered in Artifex MuPDF… CVSS 3.1HIGH 7.5
See all 66 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences