Code execution via reentrant annotation page release
Published Sep 23, 2026 · Updated Sep 23, 2026
Use-after-free in Foxit PDF Reader and PDF Editor for Windows allows attackers to execute code through a crafted PDF document. During JavaScript annotation enumeration, reentrant page-event processing releases the associated page object and later accesses the freed object. Opening the document is required; exploitation runs in the application process and can instead terminate it.
Summary
What happened
Use-after-free in Foxit PDF Reader and PDF Editor for Windows allows attackers to execute code through a crafted PDF document. During JavaScript annotation enumeration, reentrant page-event processing releases the associated page object and later accesses the freed object. Opening the document is required; exploitation runs in the application process and can instead terminate it.
The record
- CVE
- CVE-2026-91818
- Published
- Sep 23, 2026
- Updated
- Sep 23, 2026
- Vendor
- Foxit Software Company
- Product
- Foxit PDF Reader
- Classifications
- CWE-416, 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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