ZDF
Sign inSign up

Vulnerabilities

Vulnerability · 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.

Published Sep 23, 2025 · catalog updated Sep 25, 2025 · A null pointer dereference

Last checked Oct 26, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2025-55780. EPSS is 0.43%. Act only if a listed version of A null pointer dereference is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (A null pointer dereference).
  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.

Same product and reporting

Severity
High7.5
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.43%
Remediation
Vendor / distro source
Affected products
vendor n/a n/a n/a

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • vendor n/a n/a n/an/a

How to fix CVE-2025-55780

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2025-55780. EPSS is 0.43%. Act only if a listed version of A null pointer dereference is installed.

Which versions are affected?

Compare what you have installed with n/a n/a n/a n/a. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

No weakness class is stored. EPSS 0.43%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Sep 23, 2025 · EUVD

    Detected

    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.

  2. Sep 25, 2025 · EUVD

    Updated

    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.

Sources

  • CVE.orgVulnerability recordCVE-2025-55780

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2025-55780

    30-day exploitation probability 0.43%

    first.org
  • EUVDVulnerability recordEUVD-2025-30899

    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 n

    euvd.enisa.europa.eu

References

Freshness

Last verified in this catalog Oct 26, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • FIRST EPSSOct 26, 2026
  • CVE.orgOct 23, 2026
  • EUVDOct 23, 2026