CVE-2021-3909: Cloudflare Octorpki

High severity, CVSS 7.5. EPSS: 1.6% chance of exploitation in the next 30 days.

OctoRPKI does not limit the length of a connection, allowing for a slowloris DOS attack to take place which makes OctoRPKI wait forever. Specifically, the repository that OctoRPKI sends HTTP requests to will keep the connection open for a day before a response is returned, but does keep drip feeding new bytes to keep the connection alive.

Affected products

• Cloudflare Octorpki: before 1.3.0 (fixed in 1.3.0)
• Debian Debian Linux: version 11.0 only

Published 2021-11-11. Last modified 2026-06-17.