geminabox (aka Gem in a Box) before 0.13.6 has XSS, as demonstrated by uploading a gem file that has a crafted gem.homepage value in its .gemspec file.
Severity
CVSS 3.1
5.4 medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
EPSS
0.7% chance of exploitation in the next 30 days; higher than 52% of CVEs (scores of 2026-10-31)