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.

References

https://github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37

https://github.com/dadrus/heimdall/releases/tag/v0.17.14

https://github.com/dadrus/heimdall/pull/3208

https://github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943

Details

Source: Mitre, NVD

Published: 2026-05-08

Updated: 2026-05-08

Risk Information

CVSS v2

Base Score: 6.4

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

Severity: Medium

CVSS v3

Base Score: 9.1

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

Severity: Critical

CVSS v4

Base Score: 7.8

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

Severity: High