{"action":"Upgrade syncthing to 1.12.1~ds1-3 or later.","affected":[{"fixed":"1.12.1~ds1-3","introduced":"0"}],"component":"syncthing","cve_ids":[],"ecosystem":"Debian","ecosystem_qualifier":"Debian:13","exploited":false,"fixed_versions":["1.12.1~ds1-3"],"id":"tcs_01M5NFDKX86EB6A78Y4B0MSW77","modified_at":"2026-10-23T18:03:25.307352181Z","published_at":"2021-04-06T20:15:13.490Z","references":["https://osv.dev/vulnerability/DEBIAN-CVE-2021-21404","https://security-tracker.debian.org/tracker/CVE-2021-21404"],"severity":{"label":"high","score":7.5},"sources":[{"source":"osv","source_id":"DEBIAN-CVE-2021-21404#Debian:13/syncthing","url":"https://osv.dev/vulnerability/DEBIAN-CVE-2021-21404"}],"summary":"Syncthing is a continuous file synchronization program. In Syncthing before version 1.15.0, the relay server `strelaysrv` can be caused to crash and exit by sending a relay message with a negative len"}