CVE-2026-91804: Out-of-bounds Write (CWE-787) in Foxit Software Inc. Foxit PDF Editor
A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry can result in memory corruption and application crashes.
AI Analysis
Technical Summary
This vulnerability involves a heap-based out-of-bounds write in Foxit PDF Editor/Reader triggered by processing Circle annotations that contain malformed Cloudy appearance streams. The root cause is inadequate validation of the appearance geometry data, which allows memory corruption. This can result in application instability or crashes when opening maliciously crafted PDF files.
Potential Impact
Successful exploitation can cause memory corruption, potentially leading to application crashes and denial of service. The CVSS score of 7.8 indicates high severity with high impact on confidentiality, integrity, and availability. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should exercise caution when opening untrusted PDF files containing Circle annotations with Cloudy appearance streams.
CVE-2026-91804: Out-of-bounds Write (CWE-787) in Foxit Software Inc. Foxit PDF Editor
Description
A heap-based out-of-bounds write vulnerability exists in Foxit PDF Editor/Reader’s rendering of Circle annotations with malformed Cloudy appearance streams in specially crafted PDF files. Insufficient validation of the appearance geometry can result in memory corruption and application crashes.
CVSS v3.1
Score 7.8high
Affected software
Foxit Software Inc.
Foxit PDF Editor
Foxit Software Inc.
Foxit PDF Reader
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a heap-based out-of-bounds write in Foxit PDF Editor/Reader triggered by processing Circle annotations that contain malformed Cloudy appearance streams. The root cause is inadequate validation of the appearance geometry data, which allows memory corruption. This can result in application instability or crashes when opening maliciously crafted PDF files.
Potential Impact
Successful exploitation can cause memory corruption, potentially leading to application crashes and denial of service. The CVSS score of 7.8 indicates high severity with high impact on confidentiality, integrity, and availability. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
No patch or official fix information is provided in the available data. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should exercise caution when opening untrusted PDF files containing Circle annotations with Cloudy appearance streams.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Foxit
- Date Reserved
- 2026-09-15T07:34:43.393Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6ab387caf7a7c541067c166f
Added to database: 09/23/2026, 08:03:22 UTC
Last enriched: 09/23/2026, 08:18:54 UTC
Last updated: 09/24/2026, 01:57:04 UTC
Views: 9
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