Vulnerability · Published Sep 28, 2026 · Assigned by VulDB
CVE-2026-101203FastStone Image Viewer 1bpp RLE Decoder out-of-bounds write
Medium 6.3
In plain English
A medium-severity out-of-bounds write in Image Viewer from FastStone. There are no confirmed reports of exploitation so far. 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: none
Attack toolingNoneno public tooling known
Official description
A vulnerability has been found in FastStone Image Viewer up to 8.3. The impacted element is an unknown function of the component 1bpp RLE Decoder. The manipulation leads to out-of-bounds write. The attack can be initiated 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 | 8.08.18.28.3 |
Weakness: CWE-787, CWE-119 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L/E:P/RL:X/RC:R
References
- VDB-411012 | FastStone Image Viewer 1bpp RLE Decoder out-of-bounds write vdb-entry
- VDB-411012 | CTI Indicators (IOB, IOC) signature, permissions-required
- CVE-2026-101203 | CVE Analysis and Report third-party-advisory
- Submit #907575 | FastStone Soft FastStone Image Viewer 8.3 Heap-based buffer overflow (out-of-bounds write) third-party-advisory