How severe is CVE-2025-55780?

CVE-2025-55780 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-55780 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-55780?

CVE-2025-55780 affects Artifex Mupdf. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-55780?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-55780 have an EU (EUVD) identifier?

Yes. CVE-2025-55780 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30899.

When was CVE-2025-55780 published?

CVE-2025-55780 was published on 2025-09-23 and last updated on 2026-06-17.

CVE-2025-55780

CVE-2025-55780 is a high-severity vulnerability in Artifex Mupdf with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-476.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-30899
Weakness: CWE-476
Affected product: Artifex Mupdf
Published: 2025-09-23
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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 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.
How severe is CVE-2025-55780?: CVE-2025-55780 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-55780 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-55780?: CVE-2025-55780 affects Artifex Mupdf. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-55780?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-55780 have an EU (EUVD) identifier?: Yes. CVE-2025-55780 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-30899.
When was CVE-2025-55780 published?: CVE-2025-55780 was published on 2025-09-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:artifex:mupdf:*:*:*:*:*:*:*:*

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