MuPDF 1.26.4 EPUB Document break_word_for_overflow_wrap null pointer dereference

CVSS Meta Temp Score
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CTI Interest Score
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4.3$0-$5k0.00

Summaryinfo

A vulnerability was found in MuPDF 1.26.4. It has been rated as problematic. The affected element is the function break_word_for_overflow_wrap of the component EPUB Document Handler. The manipulation leads to null pointer dereference. This vulnerability is documented as CVE-2025-55780. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in MuPDF 1.26.4 and classified as problematic. This issue affects the function break_word_for_overflow_wrap of the component EPUB Document Handler. The manipulation with an unknown input leads to a null pointer dereference vulnerability. Using CWE to declare the problem leads to CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. Impacted is availability. The summary by CVE is:

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.

The advisory is shared at bugs.ghostscript.com. The identification of this vulnerability is CVE-2025-55780 since 08/16/2025. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 266050 (Linux Distros Unpatched Vulnerability : CVE-2025-55780), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (266050). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 266050
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2025-55780

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/16/2025 CVE reserved
09/24/2025 +39 days Advisory disclosed
09/24/2025 +0 days VulDB entry created
10/03/2025 +9 days VulDB entry last update

Sourcesinfo

Advisory: bugs.ghostscript.com
Status: Not defined

CVE: CVE-2025-55780 (🔒)
GCVE (CVE): GCVE-0-2025-55780
GCVE (VulDB): GCVE-100-325661

Entryinfo

Created: 09/24/2025 07:51
Updated: 10/03/2025 06:11
Changes: 09/24/2025 07:51 (54), 10/03/2025 06:11 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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