FastStone Image Viewer up to 7.5 CUR File BitCount buffer overflow

HistoryDiffrelatejsonxmlCTI

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.
6.7	$0-$5k	0.00

Summaryinfo

A vulnerability classified as critical has been found in FastStone Image Viewer up to 7.5. Impacted is an unknown function of the component CUR File Handler. Performing a manipulation of the argument BitCount results in buffer overflow. This vulnerability is cataloged as CVE-2021-26236. It is possible to initiate the attack remotely. Furthermore, there is an exploit available.

Detailsinfo

A vulnerability was found in FastStone Image Viewer up to 7.5. It has been classified as critical. This affects some unknown processing of the component CUR File Handler. The manipulation of the argument BitCount with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability.

The weakness was shared 03/19/2021. The advisory is shared at voidsec.com. This vulnerability is uniquely identified as CVE-2021-26236. It demands that the victim is doing some kind of user interaction. Technical details and a public exploit are known.

The exploit is shared for download at exploit-db.com. It is declared as proof-of-concept. The vulnerability scanner Nessus provides a plugin with the ID 208258 (FastStone Image Viewer <= 7.5 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment.

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 databases at Exploit-DB (49660) and Tenable (208258). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Vendor

FastStone

Name

Image Viewer

Version

License

free

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.0
VulDB Meta Temp Score: 6.7

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Buffer overflow
CWE: CWE-120 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Nessus ID: 208258
Nessus Name: FastStone Image Viewer <= 7.5 Multiple Vulnerabilities

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

01/25/2021 🔍
03/19/2021 +53 days 🔍
03/19/2021 +0 days 🔍
05/04/2025 +1507 days 🔍

Sourcesinfo

Advisory: voidsec.com
Status: Not defined

CVE: CVE-2021-26236 (🔍)
GCVE (CVE): GCVE-0-2021-26236
GCVE (VulDB): GCVE-100-171429
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 03/19/2021 07:04
Updated: 05/04/2025 04:08
Changes: 03/19/2021 07:04 (41), 04/02/2021 19:06 (2), 04/02/2021 19:12 (18), 10/08/2024 16:31 (17), 05/04/2025 04:08 (5)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.