{"id":"CVE-2021-3909","aliases":["DEBIAN-CVE-2021-3909","DSA-5033-1","DSA-5041-1","EUVD-2021-2322","GHSA-8cvr-4rrf-f244","GO-2022-0250","UBUNTU-CVE-2021-3909"],"status":"published","title":"Infinite open connection causes OctoRPKI to hang forever","description":"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.","severity":{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.01575,"percentile":0.75625,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-400"],"published":"2021-11-10T20:15:44Z","modified":"2026-10-23T18:03:50Z","fixes":[{"ecosystem":"Go","package":"github.com/cloudflare/cfrpki","fixed_in":["1.4.0"],"sources":["ghsa","osv"]},{"ecosystem":"Debian:12","package":"cfrpki","fixed_in":["1.4.0-1"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"fort-validator","fixed_in":["1.5.3-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"fort-validator","fixed_in":["1.5.3-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"fort-validator","fixed_in":["1.5.3-1"],"sources":["osv"]},{"ecosystem":"Debian:12","package":"rpki-client","fixed_in":["7.5-1"],"sources":["osv"]},{"ecosystem":"Debian:13","package":"rpki-client","fixed_in":["7.5-1"],"sources":["osv"]},{"ecosystem":"Debian:14","package":"rpki-client","fixed_in":["7.5-1"],"sources":["osv"]}],"affected":[{"source":"ghsa","ecosystem":"Go","package":"github.com/cloudflare/cfrpki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.0"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"cfrpki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.0-1"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"fort-validator","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.3-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"fort-validator","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.3-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"fort-validator","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.3-1"}]}]},{"source":"osv","ecosystem":"Debian:12","package":"rpki-client","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.5-1"}]}]},{"source":"osv","ecosystem":"Debian:13","package":"rpki-client","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.5-1"}]}]},{"source":"osv","ecosystem":"Debian:14","package":"rpki-client","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"7.5-1"}]}]},{"source":"osv","ecosystem":"Debian:11","package":"fort-validator","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.5.3-1~deb11u1"}]}],"versions":["1.5.0-1","1.5.1-1","1.5.2-1"],"bundled":4},{"source":"osv","ecosystem":"Debian:11","package":"cfrpki","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"1.4.2-1~deb11u1"}]}],"versions":["1.2.2-1","1.3.0-1","1.4.0-1"],"bundled":10},{"source":"osv","ecosystem":"Go","package":"github.com/cloudflare/cfrpki","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.4.0"}]}]},{"source":"osv","ecosystem":"Go","package":"github.com/cloudflare/cfrpki","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"1.4.0"}]}]}],"products":[{"vendor":"cloudflare","product":"octorpki"},{"vendor":"debian","product":"debian_linux"}],"references":[{"url":"https://github.com/cloudflare/cfrpki/security/advisories/GHSA-8cvr-4rrf-f244","tags":["x_refsource_MISC","x_transferred","Third Party Advisory","advisory","web","report"]},{"url":"https://www.debian.org/security/2021/dsa-5033","tags":["vendor-advisory","x_refsource_DEBIAN","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://www.debian.org/security/2022/dsa-5041","tags":["vendor-advisory","x_refsource_DEBIAN","x_transferred","Third Party Advisory","advisory","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-3909","tags":["advisory"]},{"url":"https://github.com/cloudflare/cfrpki/releases/tag/v1.4.0","tags":["web"]},{"url":"https://github.com/advisories/GHSA-8cvr-4rrf-f244"},{"url":"https://security-tracker.debian.org/tracker/CVE-2021-3909","tags":["advisory"]},{"url":"https://github.com/cloudflare/cfrpki","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2021-3909","tags":["report"]},{"url":"https://github.com/cloudflare/cfrpki/commit/71ac74e691dc791731f90b72710975414ecec1eb","tags":["report"]},{"url":"https://github.com/cloudflare/cfrpki/commit/dbc038f83197edc1f3360ab35af193a1557063c6","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2021-3909","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2021-3909","title":"Infinite open connection causes OctoRPKI to hang forever","description":"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.","status":"published","published":"2021-11-11T21:45:19.611Z","modified":"2024-09-16T23:06:15.208Z","cvss":[{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:33:04.020035Z"}],"euvd":[{"id":"EUVD-2021-2322","description":"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.","status":"published","published":"2021-11-11T21:45:19Z","modified":"2024-09-16T23:06:15Z","cvss":[{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-03T00:54:56.752396Z"}],"ghsa":[{"id":"GHSA-8cvr-4rrf-f244","title":"Infinite open connection causes OctoRPKI to hang forever","description":"OctoRPKI (github.com/cloudflare/cfrpki/cmd/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.\n\n## Patches\n\n## For more information\nIf you have any questions or comments about this advisory email us at security@cloudflare.com\n","status":"published","published":"2021-11-10T20:15:44Z","modified":"2023-10-02T15:56:13Z","cvss":[{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:37:07.641671Z"}],"nvd":[{"id":"CVE-2021-3909","description":"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.","status":"published","published":"2021-11-11T22:15:07.923Z","modified":"2026-06-17T04:05:58.37Z","cvss":[{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"},{"version":"2.0","score":5,"vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","level":"medium","assessor":"primary"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T14:07:00.984108Z"}],"osv":[{"id":"CVE-2021-3909","description":"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.","status":"published","published":"2021-11-11T22:15:07.923Z","modified":"2026-10-20T10:54:52.678069053Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:44:20.843843Z"},{"id":"DEBIAN-CVE-2021-3909","description":"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.","status":"published","published":"2021-11-11T22:15:07.923Z","modified":"2026-10-23T18:03:50.977348592Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"}],"updated_at":"2026-11-02T15:45:35.521549Z"},{"id":"GHSA-8cvr-4rrf-f244","title":"Infinite open connection causes OctoRPKI to hang forever","description":"OctoRPKI (github.com/cloudflare/cfrpki/cmd/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.\n\n## Patches\n\n## For more information\nIf you have any questions or comments about this advisory email us at security@cloudflare.com\n","status":"published","published":"2021-11-10T20:15:44Z","modified":"2026-07-08T06:28:03.578101407Z","cvss":[{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-400"],"updated_at":"2026-11-02T15:46:42.077781Z"},{"id":"UBUNTU-CVE-2021-3909","description":"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.","status":"withdrawn","published":"2021-11-11T22:15:00Z","modified":"2025-07-16T07:19:56.449562Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high"},{"version":"3.1","score":4.4,"vector":"CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T15:54:28.526929Z"},{"id":"DSA-5033-1","title":"fort-validator - security update","status":"published","published":"2021-12-30T00:00:00Z","modified":"2026-03-09T02:10:05.508428Z","updated_at":"2026-11-02T15:46:17.543497Z"},{"id":"DSA-5041-1","title":"cfrpki - security update","status":"published","published":"2022-01-11T00:00:00Z","modified":"2026-03-09T02:10:29.476256Z","updated_at":"2026-11-02T15:46:17.543497Z"},{"id":"GO-2022-0250","title":"Infinite open connection causes OctoRPKI to hang forever in github.com/cloudflare/cfrpki","description":"Infinite open connection causes OctoRPKI to hang forever in github.com/cloudflare/cfrpki","status":"published","published":"2024-08-21T14:30:26Z","modified":"2026-03-03T04:52:04.314826Z","updated_at":"2026-11-02T15:47:00.604718Z"}]}}