CVE-2026-57209 Details
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.
A vulnerability exists in Heimdall versions prior to 0.17.17, specifically when the application is running in proxy mode. The issue arises because Heimdall constructs the Forwarded HTTP header by directly inserting the Host header value from the incoming request, without properly sanitizing commas or semicolons. This flaw enables attackers to inject additional parameters into the Forwarded header, potentially spoofing IP addresses for upstream services.
Users can upgrade to Heimdall version 0.17.17 or later to address this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
VolerionCVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
Volerion
Assessed Oct 23, 2026CISA-ADP
Assessed Oct 29, 2026References to Advisories, Solutions, and Tools
By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.
| URL | Source(s) | Tag(s) |
|---|---|---|
| https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988 | CISA-ADP | AdvisoryExploitRemedyVendor |
| https://github.com/dadrus/heimdall/releases/tag/v0.17.17 | [email protected] | Release NotesVendor |
| https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988 | [email protected] | AdvisoryExploitRemedyVendor |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-20 | Improper Input Validation | [email protected] |
| CWE-74 | Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection') | [email protected] |
Affected Products
| Product | Versions |
|---|---|
| dadrus Heimdall | <= 0.17.16 (semver) |
CPE
Remediation
| |
Change History
2 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Oct 29, 2026 | CVE Modified | CISA-ADP |
| Oct 23, 2026 | New CVE Received | [email protected] |