What’s Vulnerable › Vulnerabilities

CVE-2026-116723: FLTK through 1.4.5 Stack Buffer Overflow via Fl_BMP_Image colors_used Field

• Severity: high (CVSS 7.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.2% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-10-26 · updated 2026-10-27
• Weakness: CWE-121

Description

FLTK through 1.4.5 contains a stack-based buffer overflow vulnerability in Fl_BMP_Image::load_bmp_() that allows attackers to corrupt stack memory by supplying an oversized BMP colors_used field. Attackers can craft BMP or ICO files with colors_used above 256 to overflow the 768-byte colormap array, causing crashes or potential code execution.

Affected products

• fltk: through 1.4.5

References

• https://github.com/fltk/fltk
• https://github.com/fltk/fltk/blob/release-1.4.5/src/Fl_BMP_Image.cxx#L255-L265
• https://github.com/fltk/fltk/commit/3a049d8262dc759cf9737339420e8457e24c0cb1
• https://github.com/fltk/fltk/issues/1632
• https://hackmd.io/@haindpwn/fltk-bmp-image-stack-heap-overflow
• https://www.vulncheck.com/advisories/fltk-through-1.4.5-stack-buffer-overflow-via-fl-bmp-image-colors-used-field

Get alerted when CVE-2026-116723 or the next vulnerability affects your stack