{"id":"CVE-2023-47124","aliases":["GHSA-8g85-whqh-cr2f","GO-2023-2381"],"url":"https://o3.security/vulnerability/CVE-2023-47124","summary":"Denial of service whith ACME HTTPChallenge in Traefik","details":"Traefik is an open source HTTP reverse proxy and load balancer. When Traefik is configured to use the `HTTPChallenge` to generate and renew the Let's Encrypt TLS certificates, the delay authorized to solve the challenge (50 seconds) can be exploited by attackers to achieve a `slowloris attack`. This vulnerability has been patch in version 2.10.6 and 3.0.0-beta5. Users are advised to upgrade. Users unable to upgrade should replace the `HTTPChallenge` with the `TLSChallenge` or the `DNSChallenge`.","published":"2023-12-04T20:20:30.727Z","modified":"2026-08-12T03:51:22.542258001Z","cvss":{"score":5.9,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Go","name":"github.com/traefik/traefik/v2","fixedVersion":"2.10.6"},{"ecosystem":"Go","name":"github.com/traefik/traefik/v3","fixedVersion":"3.0.0-beta5"}],"fix":null,"references":[{"type":"WEB","url":"https://doc.traefik.io/traefik/https/acme/#dnschallenge"},{"type":"WEB","url":"https://doc.traefik.io/traefik/https/acme/#httpchallenge"},{"type":"WEB","url":"https://doc.traefik.io/traefik/https/acme/#tlschallenge"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v2.10.6"},{"type":"WEB","url":"https://github.com/traefik/traefik/releases/tag/v3.0.0-beta5"},{"type":"WEB","url":"https://www.cloudflare.com/learning/ddos/ddos-attack-tools/slowloris"},{"type":"WEB","url":"ttps://www.cloudflare.com/learning/ddos/ddos-attack-tools/slowloris/"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/47xxx/CVE-2023-47124.json"},{"type":"ADVISORY","url":"https://github.com/traefik/traefik/security/advisories/GHSA-8g85-whqh-cr2f"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-47124"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:22.542258001Z"}}