{"action":"Upgrade libnet-cidr-perl to 0.25-1 or later.","affected":[{"fixed":"0.25-1","introduced":"0"}],"component":"libnet-cidr-perl","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:13","exploited":false,"fixed_versions":["0.25-1"],"id":"tcs_01M5NG28NDK1ZYZ4JS0QP5BG6F","modified_at":"2026-10-23T18:05:23.375902686Z","published_at":"2026-02-27T01:16:13.553Z","references":["https://osv.dev/vulnerability/DEBIAN-CVE-2021-4456","https://security-tracker.debian.org/tracker/CVE-2021-4456"],"severity":{"label":"medium","score":6.5},"sources":[{"source":"osv","source_id":"DEBIAN-CVE-2021-4456#Debian:13/libnet-cidr-perl","url":"https://osv.dev/vulnerability/DEBIAN-CVE-2021-4456"}],"summary":"Net::CIDR versions before 0.24 for Perl mishandle leading zeros in IP CIDR addresses, which may have unspecified impact. The functions `addr2cidr` and `cidrlookup` may return leading zeros in a CIDR s"}