CVE-2026-42272

Description

Heimdall is a cloud native Identity Aware Proxy and Access Control Decision service. Prior to version 0.17.14, Heimdall handles URL-encoded slashes (%2F) in a case-sensitive manner, while percent-encoding is defined to be case-insensitive. As a result, the lowercase equivalent (%2f) is not recognized and therefore not processed as expected when allow_encoded_slashes is set to off (the default setting). This discrepancy can lead to differences in how request paths are interpreted by heimdall and upstream components, which may result in authorization bypass. This issue has been patched in version 0.17.14.

References

https://github.com/dadrus/heimdall/security/advisories/GHSA-43jv-5j4x-qv67

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

https://github.com/dadrus/heimdall/pull/3207

https://github.com/dadrus/heimdall/commit/8b0de6aba23a047cfee3081df878271bb17f4351

Details

Source: Mitre, NVD

Risk Information

CVSS v2

CVSS v3

CVSS v4