PT-2021-16976 · Faststone · Faststone Image Viewer

Voidsec · Published 2021-03-18 · Updated 2021-03-22 · CVE-2021-26235

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions FastStone Image Viewer versions prior to 7.6

Description The issue arises when a user opens or views a malformed CUR file, which is mishandled by FSViewer.exe, leading to a user mode write access violation. This could potentially be exploited for a Denial of Service (DoS) or possibly to achieve code execution.

Recommendations For FastStone Image Viewer versions prior to 7.6, update to version 7.6 or later to resolve the issue. As a temporary workaround, consider avoiding the use of malformed CUR files until a patch is applied. Restrict access to untrusted image files to minimize the risk of exploitation.

Fix

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

CVE-2021-26235

Affected Products

Faststone Image Viewer

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2021-26235 · Security Note
• https://osv.dev/vulnerability/CVE-2021-26235 · Vendor Advisory
• https://voidsec.com/advisories/cve-2021-26235-faststone-image-viewer-v-7-5-user-mode-write-access-violation · Note