Integer overflow in Fltk
CVE-2026-116724
FLTK through 1.4.5 contains an integer overflow vulnerability in Fl_BMP_Image::load_bmp_() that causes undersized pixel buffer allocation from file-supplied width and height. Attackers can supply a crafted BMP or ICO file with large dimensions so row decoding writes file-derived data past the heap buffer, corrupting the application heap.
Vulnerability class: Integer Overflow
Published .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/fltk/fltk/issues/1632 (issue-tracking)
- github.com/fltk/fltk (product)
- github.com/fltk/fltk/commit/3a049d8262dc759cf9737339420e8457e24c0cb1 (patch)
- github.com/fltk/fltk/blob/release-1.4.5/src/Fl_BMP_Image.cxx (technical-description)
- hackmd.io/@haindpwn/fltk-bmp-image-stack-heap-overflow (third-party-advisory)
- www.vulncheck.com/advisories/fltk-through-1.4.5-heap-buffer-overflow-via-fl-bmp… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-116724?
- CVE-2026-116724 is a high-severity vulnerability in Fltk, classified under Integer Overflow or Wraparound. CVSS score: 7.8/10. Published 2026-10-26.
- How severe is CVE-2026-116724?
- High severity. CVSS v3 base score is 7.8 out of 10.