---
id: CVE-2026-107734
title: SumatraPDF is a multi-format reader for Windows
summary: >-
  SumatraPDF is a multi-format reader for Windows. In 3.5.2 and earlier, an
  attacker-controlled SyncTeX source filename is substituted for the %f
  placeholder in an external editor command line without safe Windows argument
  quoting, and the…
severity: none
cwe:
  - CWE-20
  - CWE-88
published: '2026-10-08'
updated: '2026-10-08'
sourceUpdated: '2026-10-08T23:16:59.357'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-107734'
references:
  - url: >-
      https://github.com/sumatrapdfreader/sumatrapdf/commit/398d23624362c60722d9709173a287ea53545b3b
    label: security-advisories@github.com
  - url: >-
      https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-jf4v-rw66-j4w2
    label: security-advisories@github.com
tags:
  - nvd
ingestedAt: '2026-10-09T00:19:50.971Z'
---

## Overview

SumatraPDF is a multi-format reader for Windows. In 3.5.2 and earlier, an attacker-controlled SyncTeX source filename is substituted for the %f placeholder in an external editor command line without safe Windows argument quoting, and the resulting command line is passed to CreateProcessW(). A user with an external editor configured or auto-detected who opens a PDF with a crafted .synctex.gz file and invokes inverse search can inject command-line flags; the resulting impact depends on the target editor interpreting those flags and can include unintended editor actions or code execution through a malicious extension. No broader impact is claimed beyond the advisory-supported conditions. No fixed version is available as of this review.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.