CVE-2026-42273: dadrus heimdall · Interpretation Conflict
Affects dadrus heimdallSource CVE Database V5
Not known to be exploited · CVSS 7.8 High : upgrade to 0.17.14 soon.
Data as of 30 Oct 2026, 11:52 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 22% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.17.14
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:NExploitation evidence
Disclosed: evidence found.
CVE published 8 May 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.
What to do
Upgrade heimdall and dadrus/heimdall to 0.17.14.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| dadrusheimdall | Affected
| Fixed in
|
GitHubdadrus/heimdallpkg:github/dadrus/heimdallOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Upgrade heimdall to version 0.17.14 or later, where the host matching logic has been corrected to be case-insensitive in accordance with HTTP standards. Patch status is confirmed by the vendor's versioning information. No additional mitigations are specified.
Description
CVE-2026-42273 is a high-severity vulnerability in dadrus heimdall, a cloud native Identity Aware Proxy and Access Control Decision service. The issue arises because heimdall versions prior to 0.17.14 perform host matching in a case-sensitive manner, whereas HTTP hostnames are case-insensitive by standard. This mismatch can cause heimdall to fail to match rules correctly when the request host differs only in letter casing, potentially leading to unintended request classification. The vulnerability has been addressed in version 0.17.14.
References
- github.com/dadrus/heimdall/security/advisories/GHSA-72h4-mxfc-jx37 (opens in a new tab)
- github.com/dadrus/heimdall/pull/3208 (opens in a new tab)
- github.com/dadrus/heimdall/commit/3d05e56a9e7ef0355f17482b4322054af4e85943 (opens in a new tab)
- github.com/dadrus/heimdall/releases/tag/v0.17.14 (opens in a new tab)