Upstream information
Description
Authelia is an open-source authentication and authorization server providing two-factor authentication and single sign-on (SSO) for applications via a web portal. In versions 4.36.0 through 4.39.19, due to lack of canonicalization of domains in very specific edge cases, an access control rule may be skipped when it should match a request. The specific conditions that could lead to a security issue for vulnerability are: 1. The specific target resource of the attack must be using the forwarded authorization integration; 2. The requested domain must have two additional segments compared to a session domain i.e. `a.b.example.com` is requested, but the session domain is `example.com`; 3. There access control rules must specify two separate rules which both contain inexact domain matches such as `*.b.example.com` and `*.example.com` i.e. wildcards, username matches, group matches; 4. The rules must be in order of most specific domain to least specific domain; 5. The second rule must be more permissive than the first rule; 6. The attacker must specifically request a URL for the more specific domain, with the second part containing one or more capitalized letters i.e. `https://a.B.example.com` and no other segment with capitalized letters; 7. The integration used must not be the Envoy ExtAuthz integration; and 8. The proxy must not canonicalize the requested host name in the relevant header before sending it to the relevant authorization endpoint. The kind of configuration used to produce this issue and result in a `bypass` rule being matched has long been highly discouraged. Essentially hosts which should be bypassed entirely should not be secured by having the proxy check them with the authorization handlers. Upgrade to 4.39.20 to receive a patch.SUSE information
Overall state of this security issue: Resolved
This issue is currently rated as having low severity.
| CVSS detail | CNA (GitHub) |
|---|---|
| Base Score | 1.3 |
| Vector | CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
| Attack Vector | Network |
| Attack Complexity | High |
| Attack Requirements | Present |
| Privileges Required | Low |
| User Interaction | None |
| Vulnerable System Confidentiality Impact | Low |
| Vulnerable System Integrity Impact | None |
| Vulnerable System Availability Impact | None |
| Subsequent System Confidentiality Impact | Low |
| Subsequent System Integrity Impact | None |
| Subsequent System Availability Impact | None |
| CVSSv4 Version | 4.0 |
List of released packages
| Product(s) | Fixed package version(s) | References |
|---|
Status of this issue by product and package
Please note that this evaluation state might be work in progress, incomplete or outdated. Also information for service packs in the LTSS phase is only included for issues meeting the LTSS criteria. If in doubt, feel free to contact us for clarification. The updates are grouped by state of their lifecycle. SUSE product lifecycles are documented on the lifecycle page.
| Product(s) | Source package | State |
|---|---|---|
| Products under general support and receiving all security fixes. | ||
| SUSE Linux Enterprise Server 16.1 | govulncheck-vulndb | Released |
| SUSE Linux Enterprise Server for SAP applications 16.1 | govulncheck-vulndb | Released |
| Products past their end of life and not receiving proactive updates anymore. | ||
| SUSE Linux Enterprise Module for Package Hub 15 SP5 | govulncheck-vulndb | Affected |
| SUSE Linux Enterprise Module for Package Hub 15 SP6 | govulncheck-vulndb | Affected |
| openSUSE Leap 15.5 | govulncheck-vulndb | Affected |
| openSUSE Leap 15.6 | govulncheck-vulndb | Affected |
SUSE Timeline for this CVE
CVE page created: Thu Jul 30 15:09:45 2026CVE page last modified: Sat Aug 1 11:37:36 2026