Open redirect in mod_auth_mellon - CVE-2019-3877

Vulnerability identifier: #VU18090

CSH Severity: Low

CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2019-3877

CWE-ID: CWE-601

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to redirect victims to arbitrary URL.

The vulnerability exists due to improper sanitization of user-supplied data in the apr_uri_parse() function within the logout URL. A remote attacker can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.

Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.

mod_auth_mellon
Amazon Linux AMI
Red Hat Enterprise Linux for IBM System z (Structure A)
Red Hat Enterprise Linux for Power 9
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for Power, big endian
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux Workstation
Red Hat Enterprise Linux Server
Red Hat Enterprise Linux Server - Extended Update Support
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for Power, big endian - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux Server - TUS
Red Hat Enterprise Linux for Power
Red Hat Enterprise Linux for x86_64
Fedora
libapache2-mod-auth-mellon (Ubuntu package)
mellon (Red Hat package)
mod_auth_mellon

Install updates from vendor's website.

mod_auth_mellon - update to 0.14.2
libapache2-mod-auth-mellon (Ubuntu package) - addressed in versions 0.13.1-1ubuntu0.1, 0.14.0-1ubuntu0.1
mellon (Red Hat package) - update to 0.14.0-2.el7_6.4
mod_auth_mellon - addressed in versions 0.14.0-5.fc29, 0.14.2-1.fc30

• https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3877
• https://github.com/Uninett/mod_auth_mellon/commit/62041428a32de402e0be6ba45fe12df6a83bedb8
• https://github.com/Uninett/mod_auth_mellon/issues/35

• Multiple vulnerabilities in mod_auth_mellon Apache module
• Ubuntu update for mod_auth_mellon
• Amazon Linux AMI update for mod24_auth_mellon
• Red Hat Enterprise Linux 8 update for Apache HTTP server (mod_auth_mellon)
• Fedora 30 update for mod_auth_mellon
• Fedora 29 update for mod_auth_mellon
• Red Hat Enterprise Linux 7 update for mod_auth_mellon