CVE-2020-15129: Open redirect in Traefik

Severity: medium (CVSS 4.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 8.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2020-07-30 · updated 2026-06-17
Weakness: CWE-601

Description

In Traefik before versions 1.7.26, 2.2.8, and 2.3.0-rc3, there exists a potential open redirect vulnerability in Traefik's handling of the "X-Forwarded-Prefix" header. The Traefik API dashboard component doesn't validate that the value of the header "X-Forwarded-Prefix" is a site relative path and will redirect to any header provided URI. Successful exploitation of an open redirect can be used to entice victims to disclose sensitive information. Active Exploitation of this issue is unlikely as it would require active header injection, however the Traefik team addressed this issue nonetheless to prevent abuse in e.g. cache poisoning scenarios.

Affected products

Traefik: before 1.7.26; from 2.2.0 before 2.2.8; 2.3.0, 2.3.0-rc1, 2.3.0-rc2 — fixed in 1.7.26, 2.2.8

How to fix

Upgrade to a fixed version: Traefik 1.7.26, 2.2.8. Check the vendor advisory for mitigations.

References

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