{"id":"CVE-2023-47124","aliases":["GHSA-8g85-whqh-cr2f","GO-2023-2381"],"title":"Traefik vulnerable to potential DDoS via ACME HTTPChallenge","summary":"Traefik vulnerable to potential DDoS via ACME HTTPChallenge","severity":"medium","cvss":5.9,"cvssVector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","vendor":"traefik","product":"github.com/traefik/traefik/v2","ecosystem":"go","affected":["github.com/traefik/traefik/v2 < 2.10.6","github.com/traefik/traefik/v3 < 3.0.0-beta5"],"patched":["github.com/traefik/traefik/v2 2.10.6","github.com/traefik/traefik/v3 3.0.0-beta5"],"published":"2023-12-05","updated":"2026-08-07","source":"OSV","sourceUrl":"https://osv.dev/vulnerability/GHSA-8g85-whqh-cr2f","references":[{"url":"https://github.com/traefik/traefik/security/advisories/GHSA-8g85-whqh-cr2f"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2023-47124"},{"url":"https://doc.traefik.io/traefik/https/acme/#dnschallenge"},{"url":"https://doc.traefik.io/traefik/https/acme/#httpchallenge"},{"url":"https://doc.traefik.io/traefik/https/acme/#tlschallenge"},{"url":"https://github.com/traefik/traefik"},{"url":"https://github.com/traefik/traefik/releases/tag/v2.10.6"},{"url":"https://github.com/traefik/traefik/releases/tag/v3.0.0-beta5"},{"url":"https://www.cloudflare.com/learning/ddos/ddos-attack-tools/slowloris"}],"tags":["osv","go"],"epss":0.00791,"epssPercentile":0.54326,"ingestedAt":"2026-08-07T19:14:16.366Z","slug":"CVE-2023-47124","body":"## Overview\n\n## Impact\n\nThere is a potential vulnerability in Traefik managing the ACME HTTP challenge.\n\nWhen Traefik is configured to use the [HTTPChallenge](https://doc.traefik.io/traefik/https/acme/#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 ([slowloris attack](https://www.cloudflare.com/learning/ddos/ddos-attack-tools/slowloris/)).\n \n## Patches\n\n- https://github.com/traefik/traefik/releases/tag/v2.10.6\n- https://github.com/traefik/traefik/releases/tag/v3.0.0-beta5\n\n## Workarounds\n\nReplace the HTTPChallenge with the [TLSChallenge](https://doc.traefik.io/traefik/https/acme/#tlschallenge) or the [DNSChallenge](https://doc.traefik.io/traefik/https/acme/#dnschallenge).\n\n## For more information\n\nIf you have any questions or comments about this advisory, please [open an issue](https://github.com/traefik/traefik/issues).\n\n## Affected packages\n\n- `github.com/traefik/traefik/v2 < 2.10.6`\n- `github.com/traefik/traefik/v3 < 3.0.0-beta5`\n\n## Remediation\n\nUpgrade to a patched release:\n\n- `github.com/traefik/traefik/v2 2.10.6`\n- `github.com/traefik/traefik/v3 3.0.0-beta5`","depth":"sunlit","depthScore":33,"depthScoreParts":{"impact":32.5,"likelihood":0.2,"exploitation":0,"ransomware":0},"changes":[]}