CVE-2021-26236
FastStone Image Viewer v.<= 7.5 is affected by a Stack-based Buffer Overflow at 0x005BDF49, affecting the CUR file parsing functionality (BITMAPINFOHEADER Structure, 'BitCount' file format field), that will end up corrupting the Structure Exception…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (1.97%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
FastStone Image Viewer v.<= 7.5 is affected by a Stack-based Buffer Overflow at 0x005BDF49, affecting the CUR file parsing functionality (BITMAPINFOHEADER Structure, 'BitCount' file format field), that will end up corrupting the Structure Exception Handler (SEH). Attackers could exploit this issue to achieve code execution when a user opens or views a malformed/specially crafted CUR file.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 1.97% probability · 80th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-787
- Affected
- faststone/image viewer
- Source
- cve@mitre.org
EPSS 2.0% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://voidsec.com/advisories/cve-2021-26236-faststone-image-viewer-v-7-5-stack-based-buffer-overflow/Exploit, Third Party Advisory
- https://voidsec.com/fuzzing-faststone-image-viewer-cve-2021-26236Exploit, Third Party Advisory
- https://www.exploit-db.com/exploits/49660Exploit, Third Party Advisory, VDB Entry
- https://voidsec.com/advisories/cve-2021-26236-faststone-image-viewer-v-7-5-stack-based-buffer-overflow/Exploit, Third Party Advisory
- https://voidsec.com/fuzzing-faststone-image-viewer-cve-2021-26236Exploit, Third Party Advisory
- https://www.exploit-db.com/exploits/49660Exploit, Third Party Advisory, VDB Entry
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.