Vulnerability Database

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Total vulnerabilities in the database

Link injection in SimpleSAMLphp — simplesamlphp / simplesamlphp

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

Background

Several scripts part of SimpleSAMLphp display a web page with links obtained from the request parameters. This allows us to enhance usability, as the users are presented with links they can follow after completing a certain action, like logging out.

Description

The following scripts were not checking the URLs obtained via the HTTP request before displaying them as the target of links that the user may click on:

  • www/logout.php
  • modules/core/www/no_cookie.php

The issue allowed attackers to display links targeting a malicious website inside a trusted site running SimpleSAMLphp, due to the lack of security checks involving the link_href and retryURL HTTP parameters, respectively. The issue was resolved by including a verification of the URLs received in the request against a white list of websites specified in the trusted.url.domains configuration option.

Affected versions

All SimpleSAMLphp versions prior to 1.14.4.

Impact

A remote attacker could craft a link pointing to a trusted website running SimpleSAMLphp, including a parameter pointing to a malicious website, and try to fool the victim into visiting that website by clicking on a link in the page presented by SimpleSAMLphp.

Resolution

Upgrade to the latest version.

Credit

This security issue was discovered and reported by John Page (hyp3rlinx).

  • Published: Jan 24, 2020
  • Updated: Apr 14, 2023
  • GHSA: GHSA-2r3v-q9x3-7g46
  • Severity: Low
  • Exploit:
  • CISA KEV:

CVSS v3:

  • Severity: Low
  • Score: 3.7
  • AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

CWEs:

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

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Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

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