CVE-2026-57209

high

Description

Heimdall is a cloud native Identity Aware Proxy and Access Control Decision service. Prior to version 0.17.17, when Heimdall operates in proxy mode, it constructs the Forwarded HTTP header after executing the matched rule pipeline by inserting the incoming request's Host header value directly into the header string without sanitizing commas or semicolons. This allows an attacker to inject additional parameters into the Forwarded header, potentially spoofing IP addresses for upstream services. This issue has been patched in version 0.17.17.

References

https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988

https://github.com/dadrus/heimdall/releases/tag/v0.17.17

https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-108749

Details

Source: Mitre, NVD

Published: 2026-10-23

Updated: 2026-10-23

Risk Information

CVSS v2

Base Score: 5

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 5.3

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 7

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N

Severity: High

EPSS

EPSS: 0.00336