CVE-2017-18121 SimpleSAMLphp XSS Vulnerability

What is CVE-2017-18121?

CVE-2017-18121 is a medium-severity cross-site scripting vulnerability in Debian Debian Linux, published on 2 Feb 2018. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

The consentAdmin module in SimpleSAMLphp through 1.14.15 is vulnerable to a Cross-Site Scripting attack, allowing an attacker to craft links that could execute arbitrary JavaScript code on the victim's web browser.

Weakness: CWE-79

Which versions are affected by CVE-2017-18121?

2 open source packages ship an affected version, including simplesamlphp/simplesamlphp. It affects 2 products.

Products include Debian Debian Linux, Simplesamlphp Simplesamlphp.

How do I fix CVE-2017-18121?

Upgrade simplesamlphp/simplesamlphp to 1.14.16 or later.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2017-18121 being exploited?

There is no known exploitation of CVE-2017-18121 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2017-18121, GHSA-fv7m-wc3v-wr3w, UBUNTU-CVE-2017-18121.