Public Date:
1691126: CVE-2019-3878 mod_auth_mellon: authentication bypass in ECP flow
A vulnerability was found in mod_auth_mellon. If Apache is configured as a reverse proxy and mod_auth_mellon is configured to only let through authenticated users (with the require valid-user directive), adding special HTTP headers that are normally used to start the special SAML ECP (non-browser based) can be used to bypass authentication.

Find out more about CVE-2019-3878 from the MITRE CVE dictionary dictionary and NIST NVD.


This issue did not affect the versions of mod_auth_mellon as shipped with Red Hat Enterprise Linux 6 as they did not include support for ECP.

CVSS v3 metrics

CVSS3 Base Score 8.1
CVSS3 Base Metrics CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
Attack Vector Network
Attack Complexity Low
Privileges Required Low
User Interaction None
Scope Unchanged
Confidentiality High
Integrity Impact High
Availability Impact None

Red Hat Security Errata

Platform Errata Release Date
Red Hat Software Collections for Red Hat Enterprise Linux 6 (httpd24-httpd) RHSA-2019:0746 2019-04-11
Red Hat Enterprise Linux 7 (mod_auth_mellon) RHSA-2019:0766 2019-04-16
Red Hat Enterprise Linux 8 (mod_auth_mellon) RHSA-2019:0985 2019-05-07
Red Hat Software Collections for Red Hat Enterprise Linux 7 (httpd24-mod_auth_mellon) RHSA-2019:0746 2019-04-11

Affected Packages State

Platform Package State
Red Hat Enterprise Linux 6 mod_auth_mellon Not affected

External References

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