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TI-2021-08094 Aliases CVE-2021-26233GHSA-r9rg-jcm6-hhww

FastStone Image Viewer <= 7.5 is affected by a user mode write access violation near NULL…

Priority LOW 36CWE-787Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-787 and the CVSS impact.

Summary

FastStone Image Viewer <= 7.5 is affected by a user mode write access violation near NULL at 0x005bdfcb, triggered when a user opens or views a malformed CUR file that is mishandled by FSViewer.exe. Attackers could exploit this issue for a Denial of Service (DoS) or possibly to achieve code execution.

Why it matters now

EPSS 0.01065 64th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:faststone:image_viewer:*:*:*:*:*:*:*:*up to 7.5VulnerableFastStone
  • cpe:2.3:a:faststone:image_viewer:*:*:*:*:*:*:*:* Versions up to 7.5 Vulnerable ·FastStone

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-26233
  2. 2026-10-03 Alias added: GHSA-r9rg-jcm6-hhww

References

Advisory 1

  • TI-2007-01864 Integer overflow in FastStone Image Viewer 2.9 allows context-dependent attackers to… CVSS 2.0HIGH 9.3
  • TI-2022-17153 Unsafe Parsing of a PNG tRNS chunk in FastStone Image Viewer through 7.5 results in a stack buffer overflow. CVSS 3.1CRITICAL 9.8
  • TI-2021-08098 FastStone Image Viewer <= 7.5 is affected by a user mode write access violation at… CVSS 3.1HIGH 7.8
  • TI-2021-08097 FastStone Image Viewer v.<= 7.5 is affected by a Stack-based Buffer Overflow at… CVSS 3.1HIGH 7.8
  • TI-2024-08464 Out-of-bounds write in FastStone Image Viewer CVSS 3.1HIGH 7.8
  • TI-2024-08463 Out-of-bounds write in FastStone Image Viewer CVSS 3.1HIGH 7.8
See all 31 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences