CVE-2026-86304 json
MojoX::Authentication versions before 0.006 for Perl allow SAML authentication bypass because parse_assertion builds Net::SAML2::Binding::POST without a trust anchor
published 2mo ago modified 2mo ago also EUVD-2026-72177
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 24%
- public exploits
- 0
- none known
Summary
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.
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 2mo ago
Exploit prediction
0.31% chance of exploitation in the next 30 days, higher than 24% of all scored CVEs (FIRST EPSS, 2026-11-11).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
References
Sources
- CVE List CVE-2026-86304
- NVD CVE-2026-86304
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