CVE-2026-57209

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/dadrus/heimdall/releases/tag/v0.17.17
https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988
https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988

Configurations

No configuration.

History

29 Oct 2026, 14:17

Type	Values Removed	Values Added
References	~~() https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988 -~~	() https://github.com/dadrus/heimdall/security/advisories/GHSA-4jgr-pg2m-m988 -

23 Oct 2026, 13:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-23 13:17

Updated : 2026-10-29 14:17

NVD link : CVE-2026-57209

Mitre link : CVE-2026-57209

CVE.ORG link : CVE-2026-57209

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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