CVE-2026-42273
High
Description
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.
SeverityHigh
CVSS7.8
Exploit probability—
ProductGithub.com/dadrus/heimdall
PublishedMay 8, 2026
First seenMay 8, 2026
Weakness typeCWE-436CWE-436CWE-178CWE-178
How to fix
Update
- github.com/dadrus/heimdall0.17.14 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| github.com/dadrus/heimdallGo | v < 0.17.14 | 0.17.14 |
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