CVE-2017-18122
mediumpriority · track · 32EPSS 0.011 · 65 %ileEUUSEPSS · scored 2026-10-27
A signature-validation bypass issue was discovered in SimpleSAMLphp through 1.14.16. A SimpleSAMLphp Service Provider using SAML 1.1 will regard as valid any unsigned SAML response containing more than one signed assertion, provided that the signature of at least one of the assertions is valid. Attributes contained in all the assertions received will be merged and the entityID of the first assertion received will be used, allowing an attacker to impersonate any user of any IdP given an assertion signed by the targeted IdP.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.8–8.1
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (6)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-j4qf-3w33-8cgcSimpleSAMLphp Signature validation bypass2022-05-14ghsa · osvUS
A signature-validation bypass issue was discovered in SimpleSAMLphp through 1.14.16. A SimpleSAMLphp Service Provider using SAML 1.1 will regard as valid any unsigned SAML response containing more than one signed assertion, provided that the signature of at least one of the assertions is valid. Attributes contained in all the assertions received will be merged and the entityID of the first assertion received will be used, allowing an attacker to impersonate any user of any IdP given an assertion signed by the targeted IdP.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (9)
External citations — patches, advisories, analysis.
- https://lists.debian.org/debian-lts-announce/2018/02/msg00008.htmlcnnvd
- https://simplesamlphp.org/security/201710-01cnnvd
- https://www.debian.org/security/2018/dsa-4127cnnvd
- https://lists.debian.org/debian-lts-announce/2018/02/msg00008.htmlenisa_euvd
- https://simplesamlphp.org/security/201710-01enisa_euvd
- https://www.debian.org/security/2018/dsa-4127enisa_euvd
- https://lists.debian.org/debian-lts-announce/2018/02/msg00008.htmlMailing ListThird Party Advisorynvd
- https://simplesamlphp.org/security/201710-01PatchVendor Advisorynvd
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