CVE-2019-3878

Public Exploit

Description

A vulnerability was found in mod_auth_mellon before v0.14.2. 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.

Categories

8.1
CVSS
Severity: High
CVSS 3.0 •
CVSS 2.0 •
EPSS 3.21% Top 15%
Vendor Advisory ubuntu.com Vendor Advisory fedoraproject.org Vendor Advisory fedoraproject.org Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com Vendor Advisory redhat.com
Affected: uninett mod_auth_mellon
Published at:
Updated at:

References

Link Tags
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3878 patch third party advisory issue tracking
https://github.com/Uninett/mod_auth_mellon/pull/196 patch third party advisory exploit
https://usn.ubuntu.com/3924-1/ third party advisory vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CNW5YMC5TLWVWNJEY6AIWNSNPRAMWPQJ/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X7NLAU7KROWNTHAYSA2S67X347F42L2I/ vendor advisory
https://access.redhat.com/errata/RHSA-2019:0746 third party advisory vendor advisory
https://access.redhat.com/errata/RHSA-2019:0766 third party advisory vendor advisory
https://access.redhat.com/errata/RHSA-2019:0985 vendor advisory
https://access.redhat.com/errata/RHBA-2019:0959 vendor advisory

Frequently Asked Questions

What is the severity of CVE-2019-3878?
CVE-2019-3878 has been scored as a high severity vulnerability.
How to fix CVE-2019-3878?
To fix CVE-2019-3878, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2019-3878 being actively exploited in the wild?
It is possible that CVE-2019-3878 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~3% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2019-3878?
CVE-2019-3878 affects uninett mod_auth_mellon.
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