VDB-263465 · CVE-2021-34973 · ZDI-21-1204

Foxit PDF Reader 11.0.1.49938 PDF File Parser 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.
4.3	$0-$5k	0.00

Summaryinfo

A vulnerability classified as problematic has been found in Foxit PDF Reader 11.0.1.49938. This issue affects some unknown processing of the component PDF File Parser. The manipulation leads to use after free. This vulnerability is referenced as CVE-2021-34973. Remote exploitation of the attack is possible. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Foxit PDF Reader 11.0.1.49938. It has been rated as problematic. This issue affects some unknown processing of the component PDF File Parser. 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. The summary by CVE is:

Foxit PDF Reader PDF File Parsing Use-After-Free Information Disclosure Vulnerability. This vulnerability allows remote attackers to disclose sensitive information on affected installations of Foxit PDF Reader. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the parsing of PDF files. The issue results from the lack of validating the existence of an object prior to performing operations on the object. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process. Was ZDI-CAN-14968.

The advisory is shared at zerodayinitiative.com. The identification of this vulnerability is CVE-2021-34973 since 06/17/2021. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading eliminates this vulnerability.

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

Productinfo

Type

Document Reader Software

Vendor

Foxit

Name

PDF Reader

Version

11.0.1.49938

License

free

Website

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

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 3.3
CNA Vector (Zero Day Initiative): 🔍

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: Yes

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: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/17/2021 🔍
05/07/2024 +1055 days 🔍
05/08/2024 +0 days 🔍
08/14/2025 +463 days 🔍

Sourcesinfo

Vendor: foxitsoftware.com

Advisory: ZDI-21-1204
Status: Confirmed

CVE: CVE-2021-34973 (🔍)
GCVE (CVE): GCVE-0-2021-34973
GCVE (VulDB): GCVE-100-263465

Entryinfo

Created: 05/08/2024 01:39
Updated: 08/14/2025 00:31
Changes: 05/08/2024 01:39 (64), 03/31/2025 11:06 (4), 08/14/2025 00:31 (12)
Complete: 🔍
Cache ID: 216::103