{"id":"CVE-2026-49284","state":"PUBLISHED","title":"SimpleSAMLphp SP accepts a response from an unexpected IdP when unsigned `Response/InResponseTo` is combined with a signed assertion lacking `SubjectConfirmationData/InResponseTo`","description":"SimpleSAMLphp versions before 1.18.6 contain an information disclosure vulnerability. Prior to 2.4.7 and 2.5.2, SimpleSAMLphp's SAML SP ACS path does not enforce the IdP selected for an SP-initiated login when unsigned Response/InResponseTo is combined with a signed assertion lacking SubjectConfirmationData/InResponseTo, allowing a response issued by one trusted IdP to be bound to SP state created for another IdP and bypass flows that route users to a specific IdP, including deployments that set enable_unsolicited to false. This issue is fixed in versions 2.4.7 and 2.5.2.","publishedAt":"2026-07-17T19:17:23.897Z","updatedAt":"2026-07-20T19:22:12.247Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["simplesamlphp simplesamlphp"],"affected":[{"vendor":"simplesamlphp","product":"simplesamlphp","versions":[{"version":"< 2.4.7","status":"affected"},{"version":">= 2.5.0-rc1, < 2.5.2","status":"affected"}]}],"references":["https://github.com/simplesamlphp/simplesamlphp/security/advisories/GHSA-q8r6-xj3f-wrrm","https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.4.7","https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.5.2"],"weaknesses":["CWE-345"],"ingestedAt":"2026-10-29T20:12:07.131Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/49xxx/CVE-2026-49284.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49284","state":"PUBLISHED","datePublished":"2026-07-17T19:17:23.897Z","dateUpdated":"2026-07-20T19:22:12.247Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-05-28T20:07:58.861Z"},"containers":{"cna":{"title":"SimpleSAMLphp SP accepts a response from an unexpected IdP when unsigned `Response/InResponseTo` is combined with a signed assertion lacking `SubjectConfirmationData/InResponseTo`","descriptions":[{"lang":"en","value":"SimpleSAMLphp versions before 1.18.6 contain an information disclosure vulnerability. Prior to 2.4.7 and 2.5.2, SimpleSAMLphp's SAML SP ACS path does not enforce the IdP selected for an SP-initiated login when unsigned Response/InResponseTo is combined with a signed assertion lacking SubjectConfirmationData/InResponseTo, allowing a response issued by one trusted IdP to be bound to SP state created for another IdP and bypass flows that route users to a specific IdP, including deployments that set enable_unsolicited to false. This issue is fixed in versions 2.4.7 and 2.5.2."}],"affected":[{"vendor":"simplesamlphp","product":"simplesamlphp","versions":[{"version":"< 2.4.7","status":"affected"},{"version":">= 2.5.0-rc1, < 2.5.2","status":"affected"}]}],"references":[{"url":"https://github.com/simplesamlphp/simplesamlphp/security/advisories/GHSA-q8r6-xj3f-wrrm","name":"https://github.com/simplesamlphp/simplesamlphp/security/advisories/GHSA-q8r6-xj3f-wrrm","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.4.7","name":"https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.4.7","tags":["x_refsource_MISC"]},{"url":"https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.5.2","name":"https://github.com/simplesamlphp/simplesamlphp/releases/tag/v2.5.2","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":7.1,"baseSeverity":"HIGH","confidentialityImpact":"LOW","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-345","lang":"en","description":"CWE-345: Insufficient Verification of Data Authenticity","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-07-17T19:17:23.897Z"},"source":{"advisory":"GHSA-q8r6-xj3f-wrrm","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-20T19:21:50.152369Z","id":"CVE-2026-49284","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-07-20T19:22:12.247Z"}}]}}}