CVE-2019-16201: Debian Linux

High severity, CVSS 7.5. EPSS: 5.1% chance of exploitation in the next 30 days.

WEBrick::HTTPAuth::DigestAuth in Ruby through 2.4.7, 2.5.x through 2.5.6, and 2.6.x through 2.6.4 has a regular expression Denial of Service cause by looping/backtracking. A victim must expose a WEBrick server that uses DigestAuth to the Internet or a untrusted network.

Affected products

• Debian Debian Linux: version 8.0 only
• Ruby-Lang Ruby: from 2.4.0, up to and including 2.4.7; from 2.5.0, up to and including 2.5.6; from 2.6.0, up to and including 2.6.4

Published 2019-11-26. Last modified 2026-06-17.