Upstream information
Description
Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.44, 3.6.15, and 3.7.0-rc.3, there is an information disclosure vulnerability in Traefik's errors (custom error pages) middleware. When the backend returns a response matching the configured status range, the middleware forwards the original request's complete header set, including Authorization, Cookie, and other authentication material, to the separate error page service rather than only the minimal context needed to render the error page. This behavior is undocumented: the documentation states only that Host is forwarded by default, so operators are not warned that sensitive credentials are shared across service boundaries. Deployments using the errors middleware with a distinct error page service may inadvertently expose end-user credentials to infrastructure that was not intended to receive them. This vulnerability is fixed in 2.11.44, 3.6.15, and 3.7.0-rc.3.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having moderate severity.
| CVSS detail | National Vulnerability Database |
|---|---|
| Base Score | 5.8 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N |
| Attack Vector | Network |
| Attack Complexity | Low |
| Privileges Required | None |
| User Interaction | None |
| Scope | Changed |
| Confidentiality Impact | Low |
| Integrity Impact | None |
| Availability Impact | None |
| CVSSv3 Version | 3.1 |
| CVSS detail | CNA (GitHub) |
|---|---|
| Base Score | 6.9 |
| Vector | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| Attack Vector | Network |
| Attack Complexity | Low |
| Attack Requirements | None |
| Privileges Required | None |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | None |
| Vulnerable System Integrity Impact | None |
| Vulnerable System Availability Impact | None |
| Subsequent System Confidentiality Impact | Low |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
List of released packages
| Product(s) | Fixed package version(s) | References |
|---|---|---|
| openSUSE Tumbleweed |
| Patchnames: openSUSE-Tumbleweed-2026-10713 openSUSE-Tumbleweed-2026-10714 |
SUSE Timeline for this CVE
CVE page created: Thu May 7 11:48:13 2026CVE page last modified: Tue May 19 18:10:43 2026