High (8.8) in ruby-lang ruby. EPSS 16% chance of exploitation in the next 30 days. Fixed in webrick 1.4.0.
The Basic authentication code in WEBrick library in Ruby before 2.2.8, 2.3.x before 2.3.5, and 2.4.x through 2.4.1 allows remote attackers to inject terminal emulator escape sequences into its log and possibly execute arbitrary commands via a crafted user name.
Severity
CVSS 3.0
8.8 high
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
16% chance of exploitation in the next 30 days; higher than 96% of CVEs (scores of 2026-10-31)