CVE-2026-25556
Double-Free Vulnerability in MuPDF Barcode Rendering Causes Crash
Publication date: 2026-02-06
Last updated on: 2026-02-24
Assigner: VulnCheck
Description
Description
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| artifex | mupdf | From 1.23.0 (inc) to 1.27.0 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-415 | The product calls free() twice on the same memory address. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2026-25556 is a double-free vulnerability in MuPDF versions 1.23.0 through 1.27.0, specifically in the function fz_fill_pixmap_from_display_list(). This function accepts a caller-owned fz_pixmap pointer but incorrectly frees the pixmap during its error handling path if an exception occurs during display list rendering.
Because the caller, including the barcode decoding function fz_decode_barcode_from_display_list, also frees the same pixmap during cleanup, this results in a double-free condition. This double-free can corrupt the heap and cause the process to crash.
The vulnerability can be triggered by processing specially crafted input that causes a rendering-time error while decoding barcodes.
How can this vulnerability impact me? :
[{'type': 'paragraph', 'content': 'This vulnerability can lead to heap corruption and cause the affected application to crash, resulting in denial of service.'}, {'type': 'paragraph', 'content': "Since the issue occurs during barcode decoding, any application using MuPDF's barcode decoding feature and processing untrusted or crafted inputs could be impacted."}, {'type': 'paragraph', 'content': 'The CVSS score of 5.9 indicates a medium severity with a high impact on availability, meaning the vulnerability primarily affects the stability and availability of the application.'}] [2]
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
I don't know
What immediate steps should I take to mitigate this vulnerability?
[{'type': 'paragraph', 'content': 'To mitigate this vulnerability, you should update MuPDF to a version later than 1.27.0 where the double-free issue in fz_fill_pixmap_from_display_list() has been fixed.'}, {'type': 'paragraph', 'content': "Additionally, if you use applications that enable MuPDF's barcode decoding feature, consider disabling barcode decoding until the update is applied to prevent triggering the vulnerability."}] [2]