Improper input validation in Traefik

CVE-2023-47106

Traefik is an open source HTTP reverse proxy and load balancer. When a request is sent to Traefik with a URL fragment, Traefik automatically URL encodes and forwards the fragment to the backend server. This violates RFC 7230 because in the origin-form the URL should only contain the absolute path and the query. When this is combined with another frontend proxy like Nginx, it can be used to bypass frontend proxy URI-based access control restrictions. This vulnerability has been addressed in versions 2.10.6 and 3.0.0-beta5. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.006 (46.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 4.8 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N.

Affected products

  • Traefik — versions 3.0.0, >= 3.0.0-beta1, < 3.0.0-beta5, < 2.10.6

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2023-47106?
CVE-2023-47106 is a medium-severity vulnerability in Traefik, classified under Improper Input Validation. CVSS score: 4.8/10. Published 2023-12-04.
How severe is CVE-2023-47106?
Medium severity. CVSS v3 base score is 4.8 out of 10.