{"url":"http://public2.vulnerablecode.io/api/packages/935952?format=json","purl":"pkg:deb/debian/puma@4.3.8-1?distro=trixie","type":"deb","namespace":"debian","name":"puma","version":"4.3.8-1","qualifiers":{"distro":"trixie"},"subpath":"","is_vulnerable":false,"next_non_vulnerable_version":"4.3.8-1+deb11u3","latest_non_vulnerable_version":"6.6.0-4","affected_by_vulnerabilities":[],"fixing_vulnerabilities":[{"url":"http://public2.vulnerablecode.io/api/vulnerabilities/47854?format=json","vulnerability_id":"VCID-q37p-vzmm-aken","summary":"Puma's Keepalive Connections Causing Denial Of Service\nThis vulnerability is related to [CVE-2019-16770](https://github.com/puma/puma/security/advisories/GHSA-7xx3-m584-x994).\n\n### Impact\n\nThe fix for CVE-2019-16770 was incomplete. The original fix only protected existing connections that had already been accepted from having their requests starved by greedy persistent-connections saturating all threads in the same process. However, new connections may still be starved by greedy persistent-connections saturating all threads in all processes in the cluster.\n\nA `puma` server which received more concurrent `keep-alive` connections than the server had threads in its threadpool would service only a subset of connections, denying service to the unserved connections.\n\n### Patches\n\nThis problem has been fixed in `puma` 4.3.8 and 5.3.1.\n\n### Workarounds\n\nSetting `queue_requests false` also fixes the issue. This is not advised when using `puma` without a reverse proxy, such as `nginx` or `apache`, because you will open yourself to slow client attacks (e.g. [slowloris](https://en.wikipedia.org/wiki/Slowloris_(computer_security))).\n\nThe fix is very small. [A git patch is available here](https://gist.github.com/nateberkopec/4b3ea5676c0d70cbb37c82d54be25837) for those using [unsupported versions](https://github.com/puma/puma/security/policy#supported-versions) of Puma.\n\n### For more information\n\nIf you have any questions or comments about this advisory:\n\n* Open an issue in [Puma](https://github.com/puma/puma).\n* To report problems with this fix or to report another vulnerability, see [our security policy.](https://github.com/puma/puma/security/policy)\n\n### Acknowledgements\n\nThank you to @MSP-Greg, @wjordan and @evanphx for their review on this issue. \n\nThank you to @ioquatix for providing a modified fork of `wrk` which made debugging this issue much easier.","references":[{"reference_url":"https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-29509.json","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}],"url":"https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2021-29509.json"},{"reference_url":"https://api.first.org/data/v1/epss?cve=CVE-2021-29509","reference_id":"","reference_type":"","scores":[{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80338","published_at":"2026-05-16T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80335","published_at":"2026-05-15T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80332","published_at":"2026-05-14T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.8029","published_at":"2026-05-12T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80138","published_at":"2026-04-08T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80164","published_at":"2026-04-11T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80102","published_at":"2026-04-02T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80122","published_at":"2026-04-04T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80109","published_at":"2026-04-07T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80145","published_at":"2026-04-09T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80274","published_at":"2026-05-11T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80278","published_at":"2026-05-09T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80262","published_at":"2026-05-07T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.8024","published_at":"2026-05-05T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80227","published_at":"2026-04-29T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80212","published_at":"2026-04-26T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80202","published_at":"2026-04-24T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80173","published_at":"2026-04-21T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.8017","published_at":"2026-04-18T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.8014","published_at":"2026-04-13T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80148","published_at":"2026-04-12T12:55:00Z"},{"value":"0.01358","scoring_system":"epss","scoring_elements":"0.80094","published_at":"2026-04-01T12:55:00Z"}],"url":"https://api.first.org/data/v1/epss?cve=CVE-2021-29509"},{"reference_url":"https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-29509","reference_id":"","reference_type":"","scores":[],"url":"https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-29509"},{"reference_url":"https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}],"url":"https://ftp.suse.com/pub/projects/security/yaml/suse-cvss-scores.yaml"},{"reference_url":"https://gist.github.com/nateberkopec/4b3ea5676c0d70cbb37c82d54be25837","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"value":"HIGH","scoring_system":"generic_textual","scoring_elements":""}],"url":"https://gist.github.com/nateberkopec/4b3ea5676c0d70cbb37c82d54be25837"},{"reference_url":"https://github.com/puma/puma","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"value":"HIGH","scoring_system":"generic_textual","scoring_elements":""}],"url":"https://github.com/puma/puma"},{"reference_url":"https://github.com/puma/puma/security/advisories/GHSA-q28m-8xjw-8vr5","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3","scoring_elements":""},{"value":"7.5","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"value":"HIGH","scoring_system":"cvssv3.1_qr","scoring_elements":""},{"value":"HIGH","scoring_system":"generic_textual","scoring_elements":""}],"url":"https://github.com/puma/puma/security/advisories/GHSA-q28m-8xjw-8vr5"},{"reference_url":"https://github.com/puma/puma/security/policy","reference_id":"","reference_type":"","scores":[{"value":"7.5","scoring_system":"cvssv3.1","scoring_elements":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"value":"HIGH","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