# CVE-2018-16648: mupdf: In Artifex MuPDF 1.13.0, the fz_append_byte function in fitz/buffer.c allows remote attackers to cause a denial of se...

CVE-2018-16648 is fixed in 2 products on 1 platform, first by mupdf 1.12.0+ds1-1ubuntu0.1~esm1, released August 22, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2018-16648
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0147
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 6, 2018

## Description

In Artifex MuPDF 1.13.0, the fz_append_byte function in fitz/buffer.c allows remote attackers to cause a denial of service (segmentation fault) via a crafted pdf file. This is caused by a pdf/pdf-device.c pdf_dev_alpha array-index underflow.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | mupdf Ubuntu 18.04.6 LTS (bionic) | 1.12.0+ds1-1ubuntu0.1~esm1 | [mupdf 1.12.0+ds1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-mupdf-1.12.0-ds1-1ubuntu0.1-esm1.md) | Aug 22, 2023 |
| Linux | mupdf-tools Ubuntu 18.04.6 LTS (bionic) | 1.12.0+ds1-1ubuntu0.1~esm1 | [mupdf-tools 1.12.0+ds1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-mupdf-tools-1.12.0-ds1-1ubuntu0.1-esm1.md) | Aug 22, 2023 |

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Data as of 2026-11-07T18:46:35Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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