CVE-2026-48794

June 19, 2026, 9:17 p.m.

1.3
Low

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.

Product(s) Impacted

Vendor Product Versions
Authelia
  • Authelia
  • 4.36.0-4.39.19

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-178
Improper Handling of Case Sensitivity
The product does not properly account for differences in case sensitivity when accessing or determining the properties of a resource, leading to inconsistent results.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a authelia authelia 4.36.0-4.39.19 / / / / / / /

References

https://github.com/authelia/authelia/commit/b6d1d60baa02f216fdb19f5dfeaf2e805829508a
https://github.com/authelia/authelia/security/advisories/GHSA-j748-h363-wqj8

Tags

[email protected]
CWE-178
2026-06-19
CVE-2026-48794

CVSS Score

1.3 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: HIGH
  • Attack Requirements: PRESENT
  • Privileges Required: LOW
  • User Interaction: NONE
  • Scope:
  • Confidentiality Impact: LOW
  • Integrity Impact: NONE
  • Availability Impact: NONE
  • Exploit Maturity: PROOF_OF_CONCEPT

    • 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

    View Vector String

Timeline

Published: June 19, 2026, 9:17 p.m.
Last Modified: June 19, 2026, 9:17 p.m.

Status : Received

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.