CVE-2017-18122 — simplesamlphp/simplesamlp…
HIGHCVE-2017-18122 is a high-severity (CVSS 8.1) CWE-347 vulnerability in simplesamlphp/simplesamlphp. A fix is available for simplesamlphp/simplesamlphp — see the affected versions and patch details below.
SimpleSAMLphp Signature validation bypass
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2017-18122 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
simplesamlphp/simplesamlphpReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | simplesamlphp/simplesamlphp | all versions | 1.14.17composer require simplesamlphp/simplesamlphp:^1.14.17 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for simplesamlphp/simplesamlphp, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update simplesamlphp/simplesamlphp to 1.14.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2017-18122 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2017-18122 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2017-18122. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2017-18122 in your dependencies?
O3 Security finds CVE-2017-18122 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.