CVE-2026-42273 PUBLISHED

Heimdall: Case-sensitive host matching may lead to policy bypass

Assigner: GitHub_M
Reserved: 26.04.2026 Published: 08.05.2026 Updated: 08.05.2026

Heimdall is a cloud native Identity Aware Proxy and Access Control Decision service. Prior to version 0.17.14, Heimdall performs host matching in a case-sensitive manner, while HTTP hostnames are case-insensitive. This discrepancy can result in heimdall failing to match a rule for a request host that differs only in letter casing, potentially causing the request to be classified differently than intended. This issue has been patched in version 0.17.14.

Metrics

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:N
CVSS Score: 7.8

Product Status

Vendor dadrus
Product heimdall
Versions
  • Version < 0.17.14 is affected

References

Problem Types

  • CWE-436: Interpretation Conflict CWE
  • CWE-178: Improper Handling of Case Sensitivity CWE