Foxit PDF Editor/PDF Reader PDF Form Fields use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
6.3$0-$5k0.38-

Summaryinfo

A vulnerability marked as problematic has been reported in Foxit PDF Editor and PDF Reader. Affected by this vulnerability is an unknown functionality of the component PDF Form Fields. The manipulation leads to use after free. This vulnerability is documented as CVE-2026-91809. The attack needs to be performed locally. There is not any exploit available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Foxit PDF Editor and PDF Reader (the affected version is unknown). This issue affects an unknown code of the component PDF Form Fields. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A use-after-free vulnerability exists in Foxit PDF Editor/Reader’s handling of malformed PDF form fields. Improper validation during field-name traversal may cause the application to access a released object, resulting in an application crash.

The advisory is shared at foxit.com. The identification of this vulnerability is CVE-2026-91809 since 09/15/2026. The exploitation is known to be easy. An attack has to be approached locally. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/23/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.3

VulDB Base Score: 4.8
VulDB Temp Score: 4.8
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (Foxit): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/15/2026 CVE reserved
09/23/2026 +8 days Advisory disclosed
09/23/2026 +0 days VulDB entry created
09/23/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: foxitsoftware.com

Advisory: foxit.com
Status: Confirmed

CVE: CVE-2026-91809 (🔒)
GCVE (CVE): GCVE-0-2026-91809
GCVE (VulDB): GCVE-100-408881

Entryinfo

Created: 09/23/2026 10:20
Changes: 09/23/2026 10:20 (61)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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