Code execution via malformed FileOpen encryption metadata
Published Sep 23, 2026 · Updated Sep 23, 2026
Untrusted pointer dereference in Foxit PDF Reader and PDF Editor for Windows allows attackers to execute code through a crafted PDF. The FileOpen plugin fails to validate metadata in a malicious FOPN_foweb encryption filter, leaving an internal pointer invalid and causing chained read and write access violations. A user must open the document; successful exploitation executes arbitrary code in the affected application's context.
Summary
What happened
Untrusted pointer dereference in Foxit PDF Reader and PDF Editor for Windows allows attackers to execute code through a crafted PDF. The FileOpen plugin fails to validate metadata in a malicious FOPN_foweb encryption filter, leaving an internal pointer invalid and causing chained read and write access violations. A user must open the document; successful exploitation executes arbitrary code in the affected application's context.
The record
- CVE
- CVE-2026-91795
- Published
- Sep 23, 2026
- Updated
- Sep 23, 2026
- Vendor
- Foxit Software Company
- Product
- Foxit PDF Reader
- Classifications
- CWE-822, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 23, 2026CVE publishedPublication date reported by the CVE source.
- Sep 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=Versions 2026.2 and earlier
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Activity data is delayed. The latest report is Sep 28, 2026.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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