CPANSA-MojoX-Authentication-2026-86304: MojoX-Authentication vulnerability
| Publisher | giterlizzi | Document category | csaf_security_advisory |
|---|---|---|---|
| Initial release date | 2026-09-06T00:00:00 | Engine | CSAF Perl Toolkit 0.26 |
| Current release date | 2026-09-06T00:00:00 | Build Date | |
| Current version | 1 | Status | final |
| CVSS v3.1 Base Score | 9.8 | Severity | Critical |
| Original language | Language | en | |
| Also referred to | |||
Vulnerability Description
MojoX::Authentication versions before 0.006 for Perl allow SAML authentication bypass because parse_assertion builds Net::SAML2::Binding::POST without a trust anchor.
parse_assertion in MojoX::Authentication::Model::SAML2 calls Net::SAML2::Binding::POST->new with no cacert, cert_text or anchors argument, then passes the returned XML to Net::SAML2::Protocol::Assertion->new_from_xml with the IdP signing certificate as cacert. In Net::SAML2 before 0.86 that certificate guards only encrypted assertions, so the signature on an unencrypted assertion is checked against the certificate the response itself carries.
An attacker starts a SAML login, then posts a response signed with a certificate of their own. The audience, InResponseTo and timestamp checks that follow are all satisfiable by the attacker, so the response authenticates any NameID it carries.
Vulnerabilities
CVE-2026-86304
Vulnerability DescriptionMojoX::Authentication versions before 0.006 for Perl allow SAML authentication bypass because parse_assertion builds Net::SAML2::Binding::POST without a trust anchor.
parse_assertion in MojoX::Authentication::Model::SAML2 calls Net::SAML2::Binding::POST->new with no cacert, cert_text or anchors argument, then passes the returned XML to Net::SAML2::Protocol::Assertion->new_from_xml with the IdP signing certificate as cacert. In Net::SAML2 before 0.86 that certificate guards only encrypted assertions, so the signature on an unencrypted assertion is checked against the certificate the response itself carries.
An attacker starts a SAML login, then posts a response signed with a certificate of their own. The audience, InResponseTo and timestamp checks that follow are all satisfiable by the attacker, so the response authenticates any NameID it carries.
| Weakness | CWE-347 : Improper Verification of Cryptographic Signature |
|---|
Product status
Known affected
| Product | Score | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| MojoX-Authentication less than 0.006 |
|
Fixed
- MojoX-Authentication greater than or equal 0.006
giterlizzi
Namespace: https://github.com/giterlizzi/
gdt@cpan.org
References
- CPANSA-MojoX-Authentication-2026-86304 JSON self
https://raw.githubusercontent.com/giterlizzi/perl-CPANSA-CSAF/develop/csaf/white/2026/cpansa-mojox-authentication-2026-86304.json - https://metacpan.org/release/POLETTIX/MojoX-Authentication-0.004/source/lib/MojoX/Authentication/Model/SAML2.pm#L188 external
https://metacpan.org/release/POLETTIX/MojoX-Authentication-0.004/source/lib/MojoX/Authentication/Model/SAML2.pm#L188 - https://metacpan.org/release/POLETTIX/MojoX-Authentication-0.006/source/Changes external
https://metacpan.org/release/POLETTIX/MojoX-Authentication-0.006/source/Changes - https://www.cve.org/CVERecord?id=CVE-2026-18089 external
https://www.cve.org/CVERecord?id=CVE-2026-18089 - CVE-2026-86304 (NVD) external
https://nvd.nist.gov/vuln/detail/CVE-2026-86304
Revision history
| Version | Date of the revision | Summary of the revision |
|---|---|---|
| 1 | Sun Sep 6 00:00:00 2026 | First release |
Sharing rules
TLP:WHITE
For the TLP version see: https://www.first.org/tlp/