CVE-2026-116724: fltk (High, CVSS 8.5)

Hands-On-Keyboard
CVE-2026-116724Highfltk
CVSS
8.5 High (v4.0)
EPSS
0.1% chance of exploitation in the next 30 days (higher than 3.8% of CVEs)
Exploited in the wild
Not on CISA’s KEV list
Public exploit
None reported in public exploit databases
Weakness
CWE-190
Vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
Published
Oct 26, 2026

What it is

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.

Description from the National Vulnerability Database.

What to do

Check whether you run fltk, then apply the vendor’s fix or mitigation from the advisories below.

Sources: NVD, FIRST EPSS, CISA KEV, and public exploit databases (availability only). ThreatRoundup reports whether public exploit code exists but never links to it: fake proof-of-concepts that infect security researchers are common. This page updates automatically.