Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1359 CNY

100%
Buy Us a Coffee

CVE-2026-42273— Heimdall: Case-sensitive host matching may lead to policy bypass

Quick assessment

Affected
dadrus heimdall
Exploitation
No confirmed in-the-wild exploitation; assess based on exposure
Recommended action
Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

Heimdall是dadrus开源的一个开源的身份感知代理和访问控制决策服务，用于云原生应用程序。 Heimdall 0.17.14之前版本存在安全漏洞，该漏洞源于以区分大小写方式执行主机匹配，而HTTP主机名不区分大小写，可能导致heimdall无法匹配仅字母大小写不同的请求主机规则，导致请求分类与预期不同。

AI Predicted 5.3 Difficulty: Easy EPSS 0.52% · P43

Possible ATT&CK Techniques 1 AI

T1190 · Exploit Public-Facing Application

Affected Version Matrix 1

VendorProduct Version RangeStatus
dadrus heimdall < 0.17.14 affected
Get alerts for future matching vulnerabilities Log in to subscribe

I. Basic Information for CVE-2026-42273

Vulnerability Information
Have questions about the vulnerability? See if Shenlong's analysis helps!
View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title
Heimdall: Case-sensitive host matching may lead to policy bypass
Source: CVE Program / CVE List V5
Vulnerability 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.
Source: CVE Program / CVE List V5
CVSS Information
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
Source: CVE Program / CVE List V5
Vulnerability Type
解释冲突
Source: CVE Program / CVE List V5
Vulnerability Title
Heimdall 安全漏洞
Source: CNNVD (China National Vulnerability Database)
Vulnerability Description
Heimdall是dadrus开源的一个开源的身份感知代理和访问控制决策服务，用于云原生应用程序。 Heimdall 0.17.14之前版本存在安全漏洞，该漏洞源于以区分大小写方式执行主机匹配，而HTTP主机名不区分大小写，可能导致heimdall无法匹配仅字母大小写不同的请求主机规则，导致请求分类与预期不同。
Source: CNNVD (China National Vulnerability Database)
CVSS Information
N/A
Source: CNNVD (China National Vulnerability Database)
Vulnerability Type
N/A
Source: CNNVD (China National Vulnerability Database)

Affected Products

Vendor Product Affected Versions CPE Subscribe
dadrus heimdall < 0.17.14 -

II. Public POCs for CVE-2026-42273

# POC Description Source Link Shenlong Link
AI-Generated POC Premium

No public POC found.

Login to generate AI POC

III. Intelligence Information for CVE-2026-42273

请登录查看更多情报信息。

Patches & Fixes for CVE-2026-42273 (2)

Vendor Advisories for CVE-2026-42273 (1)

Vendor Pages for CVE-2026-42273 (1)

Same Patch Batch · dadrus · 2026-05-08 · 3 CVEs total

CVE-2026-42272 Heimdall: Case-sensitive handling of URL-encoded slashes may lead to inconsistent path int
CVE-2026-42274 Heimdall: Authorization bypass via path normalization mismatch

IV. Related Vulnerabilities

Same product: heimdall
Same vendor: dadrus
Same weakness: CWE-436

V. Comments for CVE-2026-42273

No comments yet

Leave a comment