What’s Vulnerable › Vulnerabilities
CVE-2019-3877
- Severity: medium (CVSS 6.1 v3.0)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 2.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2019-03-27 · updated 2026-06-17
- Weakness: CWE-601
Description
A vulnerability was found in mod_auth_mellon before v0.14.2. An open redirect in the logout URL allows requests with backslashes to pass through by assuming that it is a relative URL, while the browsers silently convert backslash characters into forward slashes treating them as an absolute URL. This mismatch allows an attacker to bypass the redirect URL validation logic in apr_uri_parse function.
Affected products
- Canonical Ubuntu Linux: 18.04, 18.10
- Fedoraproject Fedora: 29
- Mod Auth Mellon Project Mod Auth Mellon: before 0.14.2 — fixed in 0.14.2
- Red Hat Enterprise Linux: 7.0
How to fix
Upgrade to a fixed version: Mod Auth Mellon Project Mod Auth Mellon 0.14.2. Check the vendor advisory for mitigations.
References
- https://access.redhat.com/errata/RHSA-2019:0766
- https://access.redhat.com/errata/RHSA-2019:3421
- 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
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CNW5YMC5TLWVWNJEY6AIWNSNPRAMWPQJ/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/X7NLAU7KROWNTHAYSA2S67X347F42L2I/
- https://usn.ubuntu.com/3924-1/
- https://access.redhat.com/errata/RHSA-2019:0766
- https://access.redhat.com/errata/RHSA-2019:3421
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3877
- https://github.com/Uninett/mod_auth_mellon/commit/62041428a32de402e0be6ba45fe12df6a83bedb8
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