CVE intelligence and bounded remediation

CVE-2017-18122 — A signature-validation bypass issue was discovered in SimpleSAMLphp through 1.14.16

High CVSS 8.1

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.

Severity
High
CVSS
8.1 (3.0)
Published
2018-02-02
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-347

Affected products

  • simplesamlphp / simplesamlphp
  • debian / debian_linux / 7.0
  • debian / debian_linux / 8.0
  • debian / debian_linux / 9.0

Matched remediation archetype

General vulnerability remediation

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Confirm the affected component, deployment paths, reachable interfaces, and enabled features from inventories and configuration, without probing production destructively.
  • Compare the advisory's affected conditions with the repository lockfiles, build manifests, artifacts, and runtime inventory.
  • Identify data sensitivity, trust boundaries, and privilege level for every confirmed affected deployment.

Remediate safely

  • Apply a vendor-supported fix or remove the affected component or feature; record the selected change and its source in the repository.
  • Update direct and transitive dependency locks, generated artifacts, deployment manifests, and asset inventories together.
  • Add a regression test for the documented unsafe condition using inert inputs and preserve rollback instructions.

Authoritative sources

Complete CVE record and remediation plan

The detailed catalog view below loads this exact record, its source evidence, and the full seven-phase agentic change plan.