High 7.8Published May 7, 2026

CVE-2026-42272Heimdall: Case-sensitive handling of URL-encoded slashes may lead to inconsistent path interpretation

Updated under an hour ago (Oct 26, 2026, 9:23 PM ET)

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Every CVE for dadrus heimdall

Exploited in the last 30 days

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.

CVSS: 7.8 HIGH (v4.0, CNA)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
Weakness (CWE): CWE-436, CWE-178
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Deferred
Record last updated: May 8, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

dadrus heimdall dadrus:heimdall (from the name)	before 0.17.14	CNA record

References

References

https://github.com/dadrus/heimdall/security/advisories/GHSA-43jv-5j4x-qv67	x-refsource-confirm
https://github.com/dadrus/heimdall/pull/3207	x-refsource-misc
https://github.com/dadrus/heimdall/commit/8b0de6aba23a047cfee3081df878271bb17f4351	x-refsource-misc
https://github.com/dadrus/heimdall/releases/tag/v0.17.14	x-refsource-misc

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.