VDB-408887 · CVE-2026-91818 · EUVD-2026-85156

Foxit PDF Editor/PDF Reader JavaScript use after free

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	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-$5k	1.82-

Summaryinfo

A vulnerability has been found in Foxit PDF Editor and PDF Reader and classified as problematic. The affected element is an unknown function of the component JavaScript Handler. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2026-91818. Local access is required to approach this attack. No exploit exists.

Detailsinfo

A vulnerability was found in Foxit PDF Editor and PDF Reader (the affected version unknown). It has been rated as problematic. This issue affects an unknown part of the component JavaScript Handler. 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 JavaScript handling of PDF annotations. Reentrant page-event processing during annotation enumeration may release the associated page object, which is subsequently accessed, resulting in an application crash.

It is possible to read the advisory at foxit.com. The identification of this vulnerability is CVE-2026-91818 since 09/15/2026. The exploitation is known to be easy. Attacking locally is a requirement. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The pricing 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.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-85156). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Type

Document Reader Software

Vendor

Foxit

Name

License

free

Website

Vendor: https://www.foxitsoftware.com/

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

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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: 🔒

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

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-2026-91818 (🔒)
GCVE (CVE): GCVE-0-2026-91818
GCVE (VulDB): GCVE-100-408887
EUVD: 🔒

Entryinfo

Created: 09/23/2026 10:23
Updated: 09/23/2026 17:56
Changes: 09/23/2026 10:23 (61), 09/23/2026 17:56 (1)
Complete: 🔍
Cache ID: 216::103