Medium severity · published Dec 4, 2023
CVE-2023-47124
Denial of service whith ACME HTTPChallenge in Traefik
5.9
CVSS
0.8%
EPSS
No
On KEV
Description
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`.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.8% · higher than 56% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TR
traefik · traefik
< 2.10.6; >= 3.0.0-beta1, < 3.0.0-beta5 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-47124
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-47124
Product
https://doc.traefik.io/traefik/https/acme/#dnschallenge
Product
https://doc.traefik.io/traefik/https/acme/#httpchallenge
Product
https://doc.traefik.io/traefik/https/acme/#tlschallenge
Release Notes
https://github.com/traefik/traefik/releases/tag/v2.10.6
Release Notes
https://github.com/traefik/traefik/releases/tag/v3.0.0-beta5
Third Party Advisory
https://github.com/traefik/traefik/security/advisories/GHSA-8g85-whqh-cr2f
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