Ubuntu Security Notices
Ubuntu Security Notices (USNs) are Canonical’s advisories for the packages that make up Ubuntu — the most widely deployed Linux distribution in the cloud. A USN maps upstream CVEs in the kernel, OpenSSL, glibc and thousands of other packages to the exact Ubuntu releases and package versions that fix them.
CSIRTS.com ingests Ubuntu Security Notices every 3 hours, normalizes each advisory into a common schema and cross-references every CVE against the CISA KEV catalog and public exploit datasets. Publishes USN advisories for Ubuntu packages. Also available via RSS, JSON API and the MCP server.