CVE-2026-91812

Foxit PDF Editor/Reader FoxitUpdater Improper Certificate Validation Local Privilege Escalation Vulnerability

Published Sep 23, 2026 CVSS 3.1 · 7.9 High EPSS < 1% KEV · Not listed
Description
A vulnerability in Foxit PDF Editor/Reader’s update mechanism allows man-in-the-middle attackers to bypass certificate validation and package integrity checks, potentially enabling arbitrary code execution with system privileges.

Analysis

AI-generated

Technical impact

A flaw in Foxit PDF Editor/Reader’s update mechanism allows a man‑in‑the‑middle attacker to bypass certificate validation and the integrity checks that normally protect the update process. The attacker can then supply a malicious update package which, when installed, grants execution of arbitrary code with system privileges on the affected machine. The weakness, categorized as improper certificate validation, is a classic example of improper verification of an issuer’s digital signature.

Affected Systems

Foxit Software Inc. releases are impacted – specifically Foxit PDF Editor and Foxit PDF Reader. No specific versions are listed in the CNA data, indicating that all current releases may be vulnerable unless a vendor patch is applied.

Risk and Exploitability

The CVSS v3 score of 7.9 signifies a high‑severity vulnerability, while the EPSS score of less than 1 % suggests low but non‑zero exploitation probability. The vulnerability is not listed in CISA’s KEV catalog. Exploitation requires the attacker to be able to intercept the update traffic, such as through a compromised network or proxy device. Once the malicious update is accepted, the attacker achieves local privilege escalation and can run code with full system permissions.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply the latest official Foxit patch for PDF Editor and PDF Reader to correct the certificate validation flaw.
  • Disable automatic updates or configure the update settings to reject unsigned or improperly signed updates until a fix is deployed.
  • Enforce network transport security by blocking untrusted update domains or requiring verified TLS connections to the official update server.

Generated by OpenCVE AI on September 23, 2026 at 15:28 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
First Time appeared Foxit
Foxit pdf Editor
Foxit pdf Reader
Microsoft
Microsoft windows
CPEs cpe:2.3:a:foxit:pdf_editor:*:*:*:*:*:*:*:*
cpe:2.3:a:foxit:pdf_reader:*:*:*:*:*:*:*:*
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*
Vendors & Products Foxit
Foxit pdf Editor
Foxit pdf Reader
Microsoft
Microsoft windows
Type Values Removed Values Added
First Time appeared Foxitsoftware
Foxitsoftware foxit Pdf Editor
Foxitsoftware foxit Reader
Vendors & Products Foxitsoftware
Foxitsoftware foxit Pdf Editor
Foxitsoftware foxit Reader
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Description A vulnerability in Foxit PDF Editor/Reader’s update mechanism allows man-in-the-middle attackers to bypass certificate validation and package integrity checks, potentially enabling arbitrary code execution with system privileges.
Title Foxit PDF Editor/Reader FoxitUpdater Improper Certificate Validation Local Privilege Escalation Vulnerability
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 7.9, 'vector': 'CVSS:3.1/AV:A/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:H'}

Weaknesses
  • CWE-295

    Improper Certificate Validation

Sources

Status
PUBLISHED
Assigner
Foxit
Published
Updated
Sep 23, 2026, 2:39 PM
Reserved
Sep 15, 2026, 7:34 AM
Status
Analyzed
Published
Sep 23, 2026, 8:17 AM
Modified
Oct 8, 2026, 2:02 PM