Vulnerability · Published Oct 26, 2026 · Assigned by VulDB
CVE-2026-116463FastStone Image Viewer Box-Average Downsampler FUN_0062d96c out-of-bounds
Medium 6.3
In plain English
A medium-severity out-of-bounds read in Image Viewer from FastStone. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 14% of all known vulnerabilities).
Severity (CVSS 3.1)6.3Medium
Exploit odds (30 days)0.2%top 85.9% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
A vulnerability was identified in FastStone Image Viewer up to 8.5. Affected is the function FUN_0062d96c of the component Box-Average Downsampler Engine. The manipulation leads to out-of-bounds read. It is possible to initiate the attack remotely. The vendor was contacted early about this disclosure but did not respond in any way.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| FastStone | Image Viewer | 8.08.18.28.38.48.5 |
Weakness: CWE-125, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:X/RL:X/RC:R
References
- VDB-426360 | FastStone Image Viewer Box-Average Downsampler FUN_0062d96c out-of-bounds vdb-entry, technical-description
- VDB-426360 | CTI Indicators (IOB, IOC, IOA) signature, permissions-required
- CVE-2026-116463 | CVE Analysis and Report third-party-advisory
- Submit #1013651 | FastStone Image Viewer 8.5 Out-of-Bounds Read third-party-advisory