---
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: high
cwe:
  - CWE-20
  - CWE-88
published: '2026-10-08'
updated: '2026-10-09'
sourceUpdated: '2026-10-09T16:17:24.383'
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
  - url: >-
      https://github.com/sumatrapdfreader/sumatrapdf/security/advisories/GHSA-jf4v-rw66-j4w2
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - cve.org
  - exploit-available
ingestedAt: '2026-10-09T00:19:50.971Z'
epss: 0.002
epssPercentile: 0.09703
vendor: sumatrapdfreader
product: sumatrapdf
affected:
  - sumatrapdf <= 3.5.2
cvss: 7.1
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-09T15:44:08.862536Z'
cvssSource: cna
---

## 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.