{"api_version":"1","generated_at":"2026-08-06T20:40:05+00:00","cve":"CVE-2026-18092","urls":{"html":"https://cve.report/CVE-2026-18092","api":"https://cve.report/api/cve/CVE-2026-18092.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-18092","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-18092"},"summary":{"title":"Net::SAML2 versions before 0.86 for Perl allow SAML authentication bypass via XML signature wrapping because new_from_xml reads assertion identity with document-wide XPath instead of the signed subtree","description":"Net::SAML2 versions before 0.86 for Perl allow SAML authentication bypass via XML signature wrapping because new_from_xml reads assertion identity with document-wide XPath instead of the signed subtree.\n\nnew_from_xml reads the NameID, attribute values, SessionIndex, audience and other identity fields with document-wide XPath, such as //saml:Assertion/saml:AttributeStatement/saml:Attribute and //saml:Subject/saml:NameID, which select the first matching element in document order rather than the element covered by the verified signature. handle_response confirms that a signature is present and, when a cacert is configured, that it chains to the CA, but XML::Sig verifies only the element named by the signature's Reference URI, so unsigned sibling assertions in the same document are not covered. An attacker who holds any one IdP-signed assertion can add an unsigned attacker-authored assertion earlier in document order; the signature still verifies and the document-order XPath returns the attacker's NameID and attributes.\n\nAny caller that passes an untrusted Response to new_from_xml can accept identity fields from an assertion the IdP never signed, even when a cacert trust anchor is configured, so a party holding one valid IdP-signed assertion can authenticate as an arbitrary user.","state":"PUBLISHED","assigner":"CPANSec","published_at":"2026-08-03 14:16:25","updated_at":"2026-08-06 18:37:08"},"problem_types":["CWE-347","CWE-347 CWE-347 Improper Verification of Cryptographic 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