CVE-2026-49283
- Source
- https://cve.org/CVERecord?id=CVE-2026-49283
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-49283.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-49283
- Aliases
- Downstream
- Published
- 2026-08-19T14:47:05Z
- Modified
- 2026-08-21T03:46:48Z
- Severity
-
- 8.7 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N CVSS Calculator
- Summary
- SimpleSAMLphp HTTP-Artifact TLS validator confusion allows cross-IdP authentication bypass
- Details
-
The SimpleSAMLphp SAML2 library is a PHP library for SAML2 related functionality. Prior to versions 4.19.3, 4.20.2, 5.0.6, and 6.2.1, the HTTPArtifact::receive() flow can treat an unsigned embedded SAML Response as cryptographically valid for the wrong identity provider. SOAPClient::addSSLValidator() attaches a TLS-based validator to the outer SOAP ArtifactResponse, while the embedded Response receives a validator that delegates to the outer message and is later checked against metadata selected from the embedded response issuer rather than necessarily the artifact issuer. SOAPClient::validateSSL() returns normally when the TLS public key does not match the key being validated, and SAML2\Message::validate() treats a validator call that does not throw as successful. In a multi-IdP federation, a malicious or lower-trust IdP can therefore provide an ArtifactResponse containing an unsigned Response that claims a higher-trust victim IdP as issuer and authenticate as arbitrary users with attacker-chosen assertion attributes, NameID, and session data. This issue is fixed in versions 4.19.3, 4.20.2, 5.0.6, and 6.2.1.
- Database specific
{ "cna_assigner": "GitHub_M", "cwe_ids": [ "CWE-295" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49283.json" }- References
-
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/49xxx/CVE-2026-49283.json
- https://github.com/simplesamlphp/saml2/security/advisories/GHSA-6929-8p9f-26jx
- https://nvd.nist.gov/vuln/detail/CVE-2026-49283
- https://github.com/simplesamlphp/saml2/commit/4a71b20d8d845579fd0a54d6449c265b40db459d
- https://github.com/simplesamlphp/saml2/commit/a2c1ac588c70d7b7998546cf32675fb113f22a5f
- https://github.com/simplesamlphp/saml2/commit/d5c213132ef671c0018a11252322034dbddd735a
- https://github.com/simplesamlphp/saml2/commit/e2df7992609964951b2a3e7d6566b7427b2a968f
Affected packages
Git / github.com/simplesamlphp/saml2
Affected ranges
- Type
- GIT
- Repo
- https://github.com/simplesamlphp/saml2
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedIntroducedIntroducedIntroducedFixedFixedFixedFixedFixedFixed
- Database specific
-
Show details
{ "extracted_events": [ { "introduced": "0" }, { "fixed": "4.19.3" }, { "introduced": "4.20.0" }, { "fixed": "4.20.2" }, { "introduced": "5.0.0" }, { "fixed": "5.0.6" }, { "introduced": "6.0.0" }, { "fixed": "6.2.1" } ], "source": [ "AFFECTED_FIELD", "REFERENCES" ] }